Frederick Chen
c2e6cadefa
https://atcoder.jp/contests/abc395 Signed-off-by: Frederick Chen <seventeen@ohdragonboi.cn>
37 lines
636 B
C++
37 lines
636 B
C++
#include <bits/stdc++.h>
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#define lo long long
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#define INF INT_MAX
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#define LLM LONG_LONG_MAX
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#define endl "\n"
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using namespace std;
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/*
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toothless. #17
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@fredcss_dev
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*/
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int n, a[1000005], b[1000005];
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bool f[100000005];
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signed main()
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{
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cin >> n;
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for (int i = 1; i <= n; i++) {
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cin >> a[i];
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b[i] = a[i];
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if (!f[a[i]]) f[a[i]] = 1;
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else {
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cout << "No";
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return 0;
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}
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}
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sort(a + 1, a + 1 + n);
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for (int i = 1; i <= n; i++) {
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if (a[i] != b[i]) {
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cout << "No";
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return 0;
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}
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}
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cout << "Yes";
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return 0;
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} |