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FZOI/#1074. 「NOIP2005」过河.cpp

@@ -0,0 +1,53 @@
+#include <bits/stdc++.h>
+#define int long long
+#define endl "\n"
+#define IMX LONG_LONG_MAX
+#define IMN LONG_LONG_MIN
+#define debug$ if(dev)
+using namespace std;
+
+/* toothless. #17 */
+
+const int N = 1e7 + 10;
+const int M = 2e3 + 5;
+const bool dev = false;
+
+int f[N], far[N], a[N], flag[N], p, s, t, n;
+
+signed main()
+{
+    cin >> p;
+    cin >> s >> t >> n;
+    if (s == t) {
+        int cont = 0, q;
+        for (int i = 1; i <= n; i++) {
+            cin >> q;
+            cont += ((q % s) == 0);
+        }
+        cout << cont;
+        return 0;
+    }
+    for (int i = 1; i <= n; i++) {
+        cin >> a[i];
+    }
+    sort(a + 1, a + 1 + n);
+    a[0] = 0;
+    f[0] = 0;
+    far[n + 1] = min(int(p - a[n]), 100);
+    p = 0;
+    for (int i = 1; i <= n; i++) {
+        far[i] = min(a[i] - a[i - 1], 90);
+        p += far[i], flag[p] = 1;
+    }
+    p += far[n + 1];
+    for (int i = 1; i <= p + 9; i++) {
+        f[i] = IMX - 1;
+        for (int j = s; j <= t; j++) {
+            if(i >= j) f[i] = min(f[i], f[i - j] + flag[i]);
+        }
+    }
+    int mn = INT_MAX - 1;
+    for (int i = p; i <= p + 9; i++) mn = min(mn, f[i]);
+    cout << mn;
+    return 0;
+}

FZOI/#1203. 「ZJOI2008」树的统计.cpp

@@ -0,0 +1,62 @@
+#include <bits/stdc++.h>
+#define int long long
+#define endl "\n"
+#define IMX LONG_LONG_MAX
+#define IMN LONG_LONG_MIN
+#define debug$ if(dev)
+using namespace std;
+
+/* toothless. #17 */
+
+const int N = 1e7 + 10;
+const int M = 2e3 + 5;
+const bool dev = false;
+
+int fa[N], dep[N], size[N], son[N], top[N], id[N], rev[N];
+int fir[N];
+
+struct edge {
+    int to, nex;
+} arr[N];
+
+void dfs1(int u, int dad)
+{
+    size[u] - 1;
+    fa[u] = dad;
+    dep[u] = dep[dad] + 1;
+    for (int i = fir[u]; i != -1; i = arr[i].nex) {
+        int v = arr[i].to;
+        if (v == dad) continue;
+        dfs1(v, u);
+        size[u] += size[v];
+        if (size[v] > size[son[u]]) son[u] = v;
+    }
+}
+
+void dfs2(int u) {
+    if (son[u]) {
+        int v = son[u];
+        id[v]++;
+        top[v] = top[u];
+        rev[t] = v;
+        dfs2(v);
+    }
+    for (int i = fir[u]; i != -1; i = arr[i].nex);
+    {
+        int v = arr[i].to;
+        if (!top[v]) {
+            id[v] = ++t;
+            top[v] = v;
+            rev[t] = v;
+            dfs2(v, u);
+        }
+    }
+}
+
+signed main()
+{
+    ios::sync_with_stdio(0);
+    cin.tie(0);
+    cout.tie(0);
+    return 0;
+}

FZOI/Fibonacci 前n项和.cpp

@@ -0,0 +1,78 @@
+#include <bits/stdc++.h>
+#define int long long
+#define endl "\n"
+#define IMX LONG_LONG_MAX
+#define IMN LONG_LONG_MIN
+#define debug$ if(dev)
+using namespace std;
+
+/* toothless. #17 */
+
+const int N = 1e7 + 10;
+const int M = 2e3 + 5;
+const bool dev = false;
+
+int n, m;
+int sum = 0;
+
+struct node
+{
+    int mat[4][4];
+};
+
+node z;
+
+node matrix_nul(node x, node y)
+{
+    memset(z.mat, 0, sizeof(z.mat));
+    for(int i = 1; i <= 3; i ++ )
+    {
+        for(int j = 1; j <= 3; j ++ )
+        {
+            for(int k = 1; k <= 3; k ++ )
+            {
+                z.mat[i][j] += (x.mat[i][k]) % m * (y.mat[k][j]) % m;
+                z.mat[i][j] %= m;
+            }
+        }
+    }
+    return z;
+}
+
+node matrix_pow(int k)
+{
+    node t, a;
+    t.mat[1][1] = 1;
+    t.mat[1][2] = 1;
+    t.mat[1][3] = 1;
+    a.mat[1][1]=1;
+	a.mat[1][2]=0;
+	a.mat[1][3]=0;
+	a.mat[2][1]=1;
+	a.mat[2][2]=1;
+	a.mat[2][3]=1;
+	a.mat[3][1]=0;
+	a.mat[3][2]=1;
+	a.mat[3][3]=0;
+    while(k)
+    {
+        if(k % 2 == 1) t = matrix_nul(t, a);
+        k /= 2;
+        a = matrix_nul(a, a);
+    }
+    return t;
+}
+
+signed main()
+{
+    ios::sync_with_stdio(0);
+    cin.tie(0);
+    cout.tie(0);
+    cin >> n >> m ;
+    node temp;
+    temp = matrix_pow(n - 1);
+    int ans = temp.mat[1][1] * 1 + temp.mat[2][1] * 0;
+    ans %= m;
+    cout << ans % m ;
+    return 0;
+}

FZOI/Tad的小蛋糕.cpp

@@ -0,0 +1,61 @@
+#include <bits/stdc++.h>
+#define int long long
+#define endl "\n"
+#define IMX LONG_LONG_MAX
+#define IMN LONG_LONG_MIN
+using namespace std;
+
+/* toothless. #17 */
+
+const int N = 1e7 + 10;
+const int M = 2e3 + 5;
+
+int n, m;
+int a[1000000];
+int qzh[1000000];
+int st[1000000][25];
+int lg[1000000];
+
+void init()
+{
+    lg[1] = 0;
+    for (int i = 2; i <= n; i++)
+    {
+        lg[i] = lg[i / 2] + 1;
+    }
+    for (int i = 1; i <= n; i++)
+    {
+        st[i][0] = qzh[i];
+    }
+    for (int k = 1; k <= lg[m]; k++)
+    {
+        for (int i = 1; i <= n; i++)
+        {
+            st[i][k] = max(st[i][k - 1], st[min(i + (1 << (k - 1)), n)][k - 1]);
+        }
+    }
+}  // ST表模板 -> 初始化
+int quary(int l, int r)
+{
+    int k = lg[r - l + 1];
+    return max(st[l][k], st[r - (1 << k) + 1][k]);
+}  // ST表模板 ->  求最大
+signed main()
+{
+    cin >> n >> m;
+    for (int i = 1; i <= n; i++)
+    {
+        cin >> a[i];
+        qzh[i] = qzh[i - 1] + a[i];
+    }
+    int maxl = -INT_MIN;
+    init();
+    for (int i = 1; i <= n; i++)
+    {
+        int r = min(i + m - 1, n);
+        int s = quary(i, r) - qzh[i - 1];
+        maxl = max(maxl, s);
+    }
+    cout << maxl;
+    return 0;
+}

FZOI/[CSP-S 2024] 决斗.cpp

@@ -0,0 +1,35 @@
+#include <bits/stdc++.h>
+#define int long long
+#define endl "\n"
+#define IMX LONG_LONG_MAX
+#define IMN LONG_LONG_MIN
+#define debug$ if(dev)
+using namespace std;
+
+/* toothless. #17 */
+
+const int N = 1e7 + 10;
+const int M = 2e3 + 5;
+const bool dev = false;
+
+int n;
+int a[N], cnt[N];
+
+signed main()
+{
+    ios::sync_with_stdio(0);
+    cin.tie(0);
+    cout.tie(0);
+    cin >> n;
+    for (int i = 1; i <= n; i++) {
+    	cin >> a[i];
+    	cnt[a[i]]++;
+    }
+    int hui = 0, ans = 0;
+    for (int i = N - 1; i >= 1; i--) {
+    	ans += min(cnt[i], hui);
+    	hui = max(hui, cnt[i]);
+    }
+    cout << n - ans;
+    return 0;
+}

FZOI/「COCI2006:2007」slikar.cpp

@@ -0,0 +1,133 @@
+#include <bits/stdc++.h>
+#define int long long
+#define endl "\n"
+#define IMX LONG_LONG_MAX
+#define IMN LONG_LONG_MIN
+using namespace std;
+
+/* toothless. #17 */
+
+const int N = 1e7 + 10;
+const int M = 2e3 + 5;
+int n, m;
+char a[55][55];
+int fx[4][2] = {1, 0, 0, 1, -1, 0, 0, -1};
+struct node
+{
+    int x;
+    int y;
+    int cnt;
+};
+int water[55][55];
+bool h_used[55][55];
+queue<node> Water;
+node startt, endd;
+queue<node> Q;
+node X[2505];
+int xid;
+void Water_Bfs()
+{
+    while (!Water.empty())
+    {
+        node noww = Water.front();
+        Water.pop();
+        noww.cnt++;
+        for (int i = 0; i < 4; i++)
+        {
+            node _next = noww;
+            _next.x += fx[i][0], _next.y += fx[i][1];
+            if (_next.x < 1 || _next.y < 1 || _next.x > n || _next.y > m)
+                continue;
+            if (h_used[_next.x][_next.y])
+                continue;
+            water[_next.x][_next.y] = min(water[_next.x][_next.y], _next.cnt);
+            Water.push(_next);
+            h_used[_next.x][_next.y] = 1;
+        }
+    }
+}
+void Ans_Bfs()
+{
+    Q.push(startt);
+    while (!Q.empty())
+    {
+        node noww = Q.front();
+        Q.pop();
+        if (water[noww.x][noww.y] <= noww.cnt)
+            continue;
+        if (noww.x == endd.x && noww.y == endd.y)
+        {
+            cout << noww.cnt;
+            return;
+        }
+        noww.cnt++;
+        for (int i = 0; i < 4; i++)
+        {
+            node _next = noww;
+            _next.x += fx[i][0], _next.y += fx[i][1];
+            if (_next.x < 1 || _next.y < 1 || _next.x > n || _next.y > m)
+                continue;
+            if (h_used[_next.x][_next.y])
+                continue;
+            if (a[_next.x][_next.y] == 'X')
+                continue;
+            Q.push(_next);
+            h_used[_next.x][_next.y] = 1;
+        }
+    }
+    cout << "KAKTUS";
+}
+signed main()
+{
+    memset(water, 127, sizeof(water));
+    cin >> n >> m;
+    for (int i = 1; i <= n; ++i)
+    {
+        for (int j = 1; j <= m; ++j)
+        {
+            cin >> a[i][j];
+            if (a[i][j] == 'S')
+            {
+                startt.x = i;
+                startt.y = j;
+                startt.cnt = 0;
+            }
+            if (a[i][j] == 'D')
+            {
+                endd.x = i;
+                endd.y = j;
+            }
+            if (a[i][j] == 'X')
+            {
+                X[xid].x = i;
+                X[xid++].y = j;
+            }
+        }
+    }
+    for (int i = 1; i <= n; i++)
+    {
+        for (int j = 1; j <= m; j++)
+        {
+            if (a[i][j] == '*')
+            {
+                node w;
+                w.x = i;
+                w.y = j;
+                w.cnt = 0;
+                Water.push(w);
+                water[i][j] = 0;
+                memset(h_used, 0, sizeof(h_used));
+                h_used[endd.x][endd.y] = 1;
+                for (int k = 0; k < xid; k++)
+                {
+                    h_used[X[k].x][X[k].y] = 1;
+                }
+                Water_Bfs();
+            }
+        }
+    }
+    water[endd.x][endd.y] = 1e8;
+    memset(h_used, 0, sizeof(h_used));
+    h_used[startt.x][startt.y] = 1;
+    Ans_Bfs();
+}

FZOI/「CSP-J2020」优秀的拆分 copy.cpp

@@ -0,0 +1,55 @@
+#include <bits/stdc++.h>
+#define int long long
+#define endl "\n"
+#define IMX LONG_LONG_MAX
+#define IMN LONG_LONG_MIN
+#define debug$ if(dev)
+using namespace std;
+
+/* toothless. #17 */
+
+const int N = 1e7 + 10;
+const int M = 2e3 + 5;
+const bool dev = false;
+
+int n;
+
+long long now = 1;
+
+bool a[N];
+
+signed main()
+{
+	scanf("%d", &n);
+
+	if (n % 2 != 0)
+	{
+		printf("-1");
+		return 0;
+	}
+	int i = 0;
+	while (now * 2 <= n)
+	{
+		now *= 2;
+		i++;
+	}
+	int i1 = i;
+	while (now > 1)
+	{
+		if (n - now >= 0)
+		{
+			a[i1] = 1;
+			n -= now;
+		}
+		i1--;
+		now /= 2;
+	}
+	for (int j = i; j >= 1; --j)
+	{
+		if (a[j] == 0)
+			continue;
+		long long ans = pow(2, j);
+		printf("%lld ", ans);
+	}
+	return 0;
+}

FZOI/「USACO2007JAN」Balanced Lineup.cpp

@@ -0,0 +1,57 @@
+#include <bits/stdc++.h>
+#define int long long
+#define endl "\n"
+#define IMX LONG_LONG_MAX
+#define IMN LONG_LONG_MIN
+using namespace std;
+
+/* toothless. #17 */
+
+const int N = 1e7 + 10;
+const int M = 2e3 + 5;
+
+int n, m;
+int a[100050], dpmax[50005][22], dpmin[50005][21];
+int LOG[50005];
+void build()
+{
+    LOG[0] = -1;
+    for (int i = 1; i <= 50005; i++)
+        LOG[i] = LOG[i >> 1] + 1;
+    for (int i = 1; i <= n; i++)
+    {
+        dpmin[i][0] = dpmax[i][0] = a[i];
+    }
+    int p = log2(n);
+    for (int k = 1; k <= p; k++)
+    {
+        for (int s = 1; s + (1 << k) <= n + 1; s++)
+        {
+            dpmax[s][k] = max(dpmax[s][k - 1], dpmax[s + (1 << (k - 1))][k - 1]);
+            dpmin[s][k] = min(dpmin[s][k - 1], dpmin[s + (1 << (k - 1))][k - 1]);
+        }
+    }
+}
+int query(int l, int r)
+{
+    int k = LOG[r - l + 1];
+    int x = max(dpmax[l][k], dpmax[r - (1 << k) + 1][k]);
+    int y = min(dpmin[l][k], dpmin[r - (1 << k) + 1][k]);
+    return x - y;
+}
+
+signed main()
+{
+    "toothless. #17";
+    cin >> n >> m;
+    for (int i = 1; i <= n; i++)
+        cin >> a[i];
+    build();
+    for (int i = 1; i <= m; i++)
+    {
+        int l, r;
+        cin >> l >> r;
+        cout << query(l, r) << endl;
+    }
+    return 0;
+}

FZOI/「模板」PYB的高斯消元.cpp

@@ -0,0 +1,50 @@
+#include <bits/stdc++.h>
+#define int long long
+#define endl "\n"
+#define IMX LONG_LONG_MAX
+#define IMN LONG_LONG_MIN
+#define debug$ if(dev)
+using namespace std;
+
+/* toothless. #17 */
+
+const int N = 1e7 + 10;
+const int M = 2e3 + 5;
+const bool dev = false;
+
+int n; 
+double a[M][M];
+
+signed main()
+{
+    ios::sync_with_stdio(0);
+    cin.tie(0);
+    cout.tie(0);
+    cin >> n;
+    for (int i = 1; i <= n; i++) {
+        for (int j = 1; j <= n + 1; j++) cin >> a[i][j];
+    }
+    for (int i = 1; i <= n; i++) {
+        int flag = 1;
+        for (int j = i; j <= n; j++)
+        {
+            if (fabs(a[j][i]) > 1e-8) {
+                flag = 0;
+                for (int k = 1; k <= n + 1; k ++ ) swap(a[i][k], a[j][k]);
+                break;
+            }
+        }
+        if (flag) {
+            cout << "No Solution" << endl ;
+            return 0;
+        }
+        for (int j = 1; j <= n; j++) {
+            if (i != j) {
+                double rate = a[j][i] / a[i][i];
+                for (int k = i; k <= n + 1; k++) a[j][k] -= a[i][k] * rate;
+            }
+        }
+    }
+    for (int i = 1; i <= n; i++) printf("%.2lf\n", a[i][n + 1] / a[i][i]);
+    return 0;
+}

FZOI/分组(groping).cpp

@@ -0,0 +1,75 @@
+#include <bits/stdc++.h>
+#define int long long
+#define endl "\n"
+#define IMX LONG_LONG_MAX
+#define IMN LONG_LONG_MIN
+using namespace std;
+
+/* toothless. #17 */
+
+const int N = 1e7 + 10;
+const int M = 2e3 + 5;
+
+// 判定函数：给定组的最小人数为x，判断是否可以分组
+bool canGroup(const vector<int>& a, int x) {
+    int n = a.size();
+    int count = 0;  // 记录已经分成的组数量
+    int group_size = 1;  // 当前组的队员人数
+
+    for (int i = 1; i < n; i++) {
+        if (a[i] == a[i - 1] + 1) {
+            // 实力值连续，当前组人数增加
+            group_size++;
+        } else {
+            // 实力值不连续，组结束
+            if (group_size >= x) {
+                count++;  // 记录一个符合条件的组
+            }
+            group_size = 1;  // 开始新组
+        }
+    }
+
+    // 更新最后一组的判断
+    if (group_size >= x) {
+        count++;
+    }
+
+    // 如果我们可以将所有人分成符合条件的组，返回true
+    return count * x <= n;
+}
+
+signed main()
+{
+    "toothless. #17";
+        int n;
+    cin >> n;  // 读取队员数量
+    vector<int> a(n);
+
+    for (int i = 0; i < n; i++) {
+        cin >> a[i];  // 读取每个队员的实力值
+    }
+
+    // 对实力值进行排序
+    sort(a.begin(), a.end());
+
+    // 使用二分查找最小组人数的最大值
+    int left = 1, right = n;
+    int ans = 1;
+
+    while (left <= right) {
+        int mid = left + (right - left) / 2;
+
+        if (canGroup(a, mid)) {
+            // 如果可以分组，尝试更大的值
+            ans = mid;
+            left = mid + 1;
+        } else {
+            // 否则尝试更小的值
+            right = mid - 1;
+        }
+    }
+
+    // 输出最小的组人数的最大值
+    cout << ans << endl;
+    return 0;
+}

FZOI/区间最大值.cpp

@@ -0,0 +1,51 @@
+#include <bits/stdc++.h>
+#define int long long
+#define endl "\n"
+#define IMX LONG_LONG_MAX
+#define IMN LONG_LONG_MIN
+using namespace std;
+
+/* toothless. #17 */
+
+const int N = 1e7 + 10;
+const int M = 2e3 + 5;
+
+int n, m;
+int a[100050], dpmax[100050][100];
+int LOG[500005];
+void build()
+{
+    LOG[0] = -1;
+    for (int i = 1; i <= 500005; i++)
+        LOG[i] = LOG[i >> 1] + 1;
+    for (int i = 1; i <= n; i++) {
+        dpmax[i][0] = a[i];
+    }
+    int p = log2(n);
+    for (int k = 1; k <= p; k++) {
+        for (int s = 1; s + (1 << k) <= n + 1; s++) {
+            dpmax[s][k] = max(dpmax[s][k - 1], dpmax[s + (1 << (k - 1))][k - 1]);
+        }
+    }
+}
+int query(int l, int r)
+{
+    int k = LOG[r - l + 1];
+    int x = max(dpmax[l][k], dpmax[r - (1 << k) + 1][k]);
+    return x;
+}
+
+signed main()
+{
+    "toothless. #17";
+    cin >> n >> m;
+    for (int i = 1; i <= n; i++)
+        cin >> a[i];
+    build();
+    for (int i = 1; i <= m; i++) {
+        int l, r;
+        cin >> l >> r;
+        cout << query(l, r) << endl;
+    }
+    return 0;
+}

FZOI/去重.cpp

@@ -0,0 +1,32 @@
+#include <bits/stdc++.h>
+#define int long long
+#define endl "\n"
+#define IMX LONG_LONG_MAX
+#define IMN LONG_LONG_MIN
+#define debug$ if(dev)
+using namespace std;
+
+/* toothless. #17 */
+
+const int N = 1e7 + 10;
+const int M = 2e3 + 5;
+const bool dev = false;
+
+int n;
+int a[N];
+map<int, bool> mp;
+
+signed main()
+{
+    cin >> n;
+    for (int i = 1; i <= n; i ++ ) {
+        cin >> a[i];
+    }
+    for (int i = 1; i <= n; i ++ ) {
+        if (!mp[a[i]]) {
+            cout << a[i] << " ";
+            mp[a[i]] = true;
+        }
+    }
+    return 0;
+}

FZOI/找拖后腿的.cpp

@@ -0,0 +1,38 @@
+#include <bits/stdc++.h>
+#define int long long
+#define endl "\n"
+#define IMX LONG_LONG_MAX
+#define IMN LONG_LONG_MIN
+#define debug$ if(dev)
+using namespace std;
+
+/* toothless. #17 */
+
+const int N = 1e7 + 10;
+const int M = 2e3 + 5;
+const bool dev = false;
+
+int n;
+
+struct stu
+{
+    int id, sc;
+} name[N];
+
+
+int g;
+
+signed main()
+{
+    cin >> n;
+    for (int i = 1; i <= n; i++) {
+        name[i].id = i;
+        cin >> name[i].sc;
+        g += name[i].sc;
+    }
+    g /= n;
+    for (int i = 1; i <= n; i++) {
+        if(name[i].sc < g) cout << name[i].id << " ";
+    }
+    return 0;
+}

FZOI/插入.cpp

@@ -0,0 +1,32 @@
+#include <bits/stdc++.h>
+#define int long long
+#define endl "\n"
+#define IMX LONG_LONG_MAX
+#define IMN LONG_LONG_MIN
+#define debug$ if(dev)
+using namespace std;
+
+/* toothless. #17 */
+
+const int N = 1e7 + 10;
+const int M = 2e3 + 5;
+const bool dev = false;
+
+int n;
+int a[N];
+int m;
+
+signed main()
+{
+    cin >> n;
+    for (int i = 1; i <= n; i++) {
+        cin >> a[i];
+    }
+    cin >> m;
+    a[n + 1] = m;
+    sort(a + 1, a + n + 2);
+    for (int i = 1; i <= n + 1; i++) {
+        cout << a[i] << " ";
+    }
+    return 0;
+}

FZOI/数的计数 + 输出.cpp

@@ -0,0 +1,111 @@
+#include <bits/stdc++.h>
+#define int long long
+#define endl "\n"
+#define IMX LONG_LONG_MAX
+#define IMN LONG_LONG_MIN
+#define debug$ if (dev)
+using namespace std;
+
+/* toothless. #17 */
+
+const int N = 1e7 + 10;
+const int M = 2e3 + 5;
+const bool dev = false;
+
+string s;
+int len, last, pre, x, flag, cs;
+char ch;
+vector<string> lstr, rstr;
+
+bool iszf(char ch)
+{
+    return ch == '+' || ch == '-' || ch == '*' || ch == '/';
+}
+
+bool is_num(char s)
+{
+    return s >= '0' && s <= '9';
+}
+
+bool is_str(const std::string &s)
+{
+    char *endptr;
+    strtod(s.c_str(), &endptr);
+    return !(*endptr == '\0');
+}
+
+int renum(string s)
+{
+    string t = s.substr(0, s.size());
+    return stoi(t);
+}
+void print()
+{
+    int ll = lstr.size();
+    for (int i = 0; i < ll; i ++ )
+        cout << lstr[i] << ' ';
+    cout << endl ;
+    ll = rstr.size();
+    for (int i = 0; i < ll; i ++ )
+        cout << rstr[i] << ' ';
+    cout << endl ;
+}
+
+bool is_ch(char ch)
+{
+    return (ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z');
+}
+signed main()
+{
+    ch = ' ';
+    getline(cin, s);
+    len = s.size();
+    for (int i = 0; i < s.size(); i++)
+    {
+        if (!(is_num(s[i])) && !iszf(s[i]) && is_ch(s[i]))
+            ch = s[i];
+        if (s[i] == '=')
+        {
+            flag = 1;
+            lstr.push_back(s.substr(last, i - last));
+            last = i + 1;
+            pre = i;
+        }
+        if (iszf(s[i]))
+        {
+            string wxh = s.substr(last, i - last);
+            if (wxh.size() == 1 && is_str(wxh))
+            {
+                wxh.insert(0, "1");
+            }
+            if (!flag)
+                lstr.push_back(wxh);
+            else
+                rstr.push_back(wxh);
+            last = i;
+        }
+    }
+    string wty = s.substr(last, s.size() - last);
+    if (wty.size() == 1 && is_str(wty))
+        wty.insert(0, "1");
+    rstr.push_back(wty);
+    int l = lstr.size();
+    for (int i = 0; i < l; i ++ )
+    {
+        if (!is_str(lstr[i]))
+            cs += stod(lstr[i]);
+        else
+            x -= renum(lstr[i]);
+    }
+    l = rstr.size();
+    for (int i = 0; i < l; i ++ )
+    {
+        if (!is_str(rstr[i]))
+            cs -= stod(rstr[i]);
+        else
+            x += renum(rstr[i]);
+    }
+    double cnt = cs * 1.0 / (x == 0 ? 1 : x);
+    printf("%c=%.3lf", ch, cnt);
+    return 0;
+}

FZOI/纪念品分组.cpp

@@ -0,0 +1,35 @@
+#include <bits/stdc++.h>
+#define int long long
+#define endl "\n"
+#define IMX LONG_LONG_MAX
+#define IMN LONG_LONG_MIN
+#define debug$ if(dev)
+using namespace std;
+
+/* toothless. #17 */
+
+const int N = 1e7 + 10;
+const int M = 2e3 + 5;
+const bool dev = false;
+
+int w, ans = 0;
+int n, a[N];
+int l, r;
+
+signed main()
+{
+    cin >> w >> n;
+    for (int i = 1; i <= n; i++) cin >> a[i];
+    sort(a + 1, a + 1 + n);
+    l = 1;
+    r = n;
+    while (l <= r) {
+        if (a[l] + a[r] <= w) {
+            l++, r--, ans++;
+        } else {
+            r--, ans++;
+        }
+    }
+    cout << ans;
+    return 0;
+}

FZOI/菲波拉契数列.cpp

@@ -0,0 +1,77 @@
+#include <bits/stdc++.h>
+#define int long long
+#define endl "\n"
+#define IMX LONG_LONG_MAX
+#define IMN LONG_LONG_MIN
+#define debug$ if(dev)
+using namespace std;
+
+/* toothless. #17 */
+
+const int N = 1e7 + 10;
+const int M = 2e3 + 5;
+const bool dev = false;
+
+int n, m;
+int sum = 0;
+
+struct node
+{
+    int mat[3][3];
+};
+
+node z;
+
+node matrix_nul(node x, node y)
+{
+    memset(z.mat, 0, sizeof(z.mat));
+    for(int i = 1; i <= 2; i ++ )
+    {
+        for(int j = 1; j <= 2; j ++ )
+        {
+            for(int k = 1; k <= 2; k ++ )
+            {
+                z.mat[i][j] += (x.mat[i][k]) * (y.mat[k][j]);
+                z.mat[i][j];
+            }
+        }
+    }
+    return z;
+}
+
+node matrix_pow(int k)
+{
+    node t, a;
+    t.mat[1][1] = 1;
+    t.mat[1][2] = 0;
+    t.mat[2][1] = 0;
+    t.mat[2][2] = 1;
+    a.mat[1][1] = 1;
+    a.mat[1][2] = 1;
+    a.mat[2][1] = 1;
+    a.mat[2][2] = 0;
+    while(k)
+    {
+        if(k % 2 == 1) t = matrix_nul(t, a);
+        k /= 2;
+        a = matrix_nul(a, a);
+    }
+    return t;
+}
+
+signed main()
+{
+    ios::sync_with_stdio(0);
+    cin.tie(0);
+    cout.tie(0);
+    cin >> n >> m ;
+    for(int i = 1; i <= n; i ++ )
+    {
+        node temp;
+        temp = matrix_pow(i - 1);
+        int ans = temp.mat[1][1] * 1 + temp.mat[2][1] * 0;
+        ans;
+        cout << ans << " " ;
+    }
+    return 0;
+}

FZOI/计算器的改良.cpp

@@ -0,0 +1,57 @@
+#include <iostream>
+#include <cstdio>
+using namespace std;
+char c, a;
+int f = 1, now = 1, k, b, x;
+bool r;
+int main()
+{
+    while (cin >> c)
+    {
+        if (c == '-')
+        {
+            b += now * f * x;
+            x = 0;
+            f = -1;
+            r = 0;
+        }
+        if (c == '+')
+        {
+            b += now * f * x;
+            x = 0;
+            f = 1;
+            r = 0;
+        }
+        if (c == '=')
+        {
+            b += now * f * x;
+            x = 0;
+            f = 1;
+            now = -1;
+            r = 0;
+        }
+        if (c >= 'a' && c <= 'z')
+        {
+            if (r)
+            {
+                k += now * f * x;
+                x = 0;
+            }
+            else
+                k += now * f;
+            a = c;
+            r = 0;
+        }
+        if (c >= '0' && c <= '9')
+        {
+            x = x * 10 + c - '0';
+            r = 1;
+        }
+    }
+    b += now * f * x;
+    double ans = double(-b * 1.0 / k);
+    if (ans == -0.0)
+        ans = 0;
+    printf("%c=%.3lf", a, ans);
+    return 0;
+}

FZOI/银行卡.cpp

@@ -0,0 +1,61 @@
+#include <bits/stdc++.h>
+#define int long long
+#define endl "\n"
+#define IMX LONG_LONG_MAX
+#define IMN LONG_LONG_MIN
+using namespace std;
+
+/* toothless. #17 */
+
+int n, pre, len;
+string s;
+
+int f(int n)
+{
+    int sum = 0;
+    while (n)
+    {
+        sum += n % 10;
+        n /= 10;
+    }
+    return sum;
+}
+
+int Get_ans(string s)
+{
+    int cnt = 0, sum = 0;
+    for (int i = len - 2; i >= 0; i--)
+    {
+        ++cnt;
+        if (cnt & 1)
+            sum += f((s[i] - '0') * 2);
+        else
+            sum += s[i] - '0';
+    }
+    return sum * 9 % 10;
+}
+
+signed main()
+{
+    cin >> n >> s;
+    len = s.size();
+    for (int i = 0; i < len; i++)
+    {
+        if (s[i] == 'x')
+        {
+            pre = i;
+            break;
+        }
+    }
+    for (char i = '0'; i <= '9'; i++)
+    {
+        s[pre] = i;
+        int ans = Get_ans(s);
+        if (ans == s[len - 1] - '0')
+        {
+            cout << i;
+            return 0;
+        }
+    }
+    return 0;
+}

Luogu/P1219 [USACO1.5] 八皇后 Checker Challenge.cpp

@@ -0,0 +1,60 @@
+#include <bits/stdc++.h>
+#define int long long
+#define endl "\n"
+#define IMX LONG_LONG_MAX
+#define IMN LONG_LONG_MIN
+#define debug$ if(dev)
+using namespace std;
+
+const int N = 1e7 + 10;
+const int M = 2e3 + 5;
+const bool dev = false;
+
+/* toothless. #17 */
+
+int a[N], b[N], c[N], d[N];
+int total;
+int n;
+
+void print()
+{
+    if (total <= 2)
+    {
+        for (int k = 1; k <= n; k++)
+            cout << a[k] << " ";
+        cout << endl;
+    }
+    total++;
+}
+void queen(int i)
+{
+    if (i > n)
+    {
+        print();
+        return;
+    }
+    else
+    {
+        for (int j = 1; j <= n; j++)
+        {
+            if ((!b[j]) && (!c[i + j]) && (!d[i - j + n]))
+            {
+                a[i] = j;
+                b[j] = 1;
+                c[i + j] = 1;
+                d[i - j + n] = 1;
+                queen(i + 1);
+                b[j] = 0;
+                c[i + j] = 0;
+                d[i - j + n] = 0;
+            }
+        }
+    }
+}
+signed main()
+{
+    cin >> n;
+    queen(1);
+    cout << total;
+    return 0;
+}

Luogu/【模板】排序.cpp

@@ -0,0 +1,23 @@
+#include <bits/stdc++.h>
+#define int long long
+#define endl "\n"
+#define IMX LONG_LONG_MAX
+#define IMN LONG_LONG_MIN
+using namespace std;
+
+/* toothless. #17 */
+
+const int N = 1e7 + 10;
+const int M = 2e3 + 5;
+
+int a[N];
+
+signed main()
+{
+    int n;
+    cin >> n ;
+    for(int i = 1; i <= n; i ++ ) cin >> a[i] ;
+    sort(a + 1, a + 1 + n);
+    for(int i = 1; i <= n; i ++ ) cout << a[i] << " " ;
+    return 0;
+}