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https://github.com/wczffl-503/OI-Codes.git
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53 lines
919 B
C++
53 lines
919 B
C++
#include <algorithm>
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#include <iostream>
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#include <iomanip>
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#include <cstring>
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#include <cstdio>
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#include <stack>
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#include <ctime>
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#include <cmath>
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#include <queue>
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typedef long long l;
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typedef double d;
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typedef char c;
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using namespace std;
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int n,m,x,y;
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char map[505][505];
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int vis[505][505];
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int dx[8]={+1,+0,-1,-0,+1,+1,-1,-1};
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int dy[8]={+0,+1,-0,-1,-1,+1,-1,+1};
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int res=0;
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struct point{
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int x;
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int y;
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};
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void bfs(){
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queue<point> que;
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que.push({x,y});
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vis[x][y]=0;
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while(!que.empty()){
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point p=que.front();
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que.pop();
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for(int i=0;i<8;i++){
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int tx=p.x+dx[i];
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int ty=p.y+dy[i];
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if(tx>=1 && tx<=n && ty>=1 && ty<=m && map[tx][ty]!='*' && vis[tx][ty]==0){
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que.push({tx,ty});
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vis[tx][ty]=vis[p.x][p.y]+1;
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res=max(vis[tx][ty],res);
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}
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}
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}
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}
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int main(){
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cin >>n>>m>>x>>y;
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for(int i=1;i<=n;i++){
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for(int j=1;j<=m;j++){
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cin >>map[i][j];
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}
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}
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bfs();
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cout <<res;
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return 0;
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}
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