Submission #1128522

#	Time	Username	Problem	Language	Result	Execution time	Memory
1128522		erasyl123	Bomb (IZhO17_bomb)	C++20	0 / 100	2 ms	584 KiB

bomb

#include <bits/stdc++.h>
#define int long long
#define boost ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
using namespace std;
const int N = 2505;
const int inf = 1e9;
const int mod=1e9+7;
struct edge{
    int pos,val,t;
};
int dp[N][N];
string c[N];
int dp1[N][N];
int n,m;
vector<pair<int,int> >v[N];
int ch(int mid){
    int ok=0;
    for(int k=0;k<v[mid].size();k++){
            int cnt=0;
            int i=v[mid][k].first;
            int j=v[mid][k].second;
            for(int y=1;y+i-1<=n;y++){
                for(int x=1;x+j-1<=m;x++){
                    int x1=x+(j-1);
                    int y1=y+(i-1);
                    int cnt=dp[y1][x1]-dp[y1][x - 1]-dp[y - 1][x1]+dp[y - 1][x - 1];
                    if(cnt==i*j){
                        dp1[y][x]++;
                        dp1[y1+1][x]--;
                        dp1[y][x1+1]--;
                        dp1[y1+1][x1+1]++;
                    }
                }
            }
            int cnt1=0;
            for(int y=1;y<=n;y++){
                for(int x=1;x<=m;x++){
                    dp1[y][x]+=dp1[y-1][x]+dp1[y][x-1]-dp1[y-1][x-1];
                    if(dp1[y][x]>0){
                        cnt1++;
                    }
                }
            }
            if(cnt1==dp[n][m]){
                ok=1;
            }
            for(int i=1;i<=n;i++){
                for(int j=1;j<=m;j++){
                    dp1[i][j]=0;
                }
            }
            if(ok==1){
                break;
            }
    }
    return ok;
}
signed main(){
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
     boost 
    cin>>n>>m;
    for(int i=1;i<=n;i++){
            cin>>c[i];
            for(int j=0;j<m;j++){
            int x=0;
            if(c[i][j]=='1'){
                x=1;
            }
            dp[i][j+1]=dp[i-1][j+1]+dp[i][j]-dp[i-1][j]+x;
            }
    }
    int mx = m, mx1 = n;
    for(int i = 1; i <= n; i++) {
        int cnt = 0;
        for(int j = 0; j < m; j++) {
            if(c[i][j] == '1')cnt ++;
            else if(j > 0 && c[i][j - 1] == '1' && c[i][j] == '0') {
                mx = min(mx, cnt);
                cnt = 0;
            }
        }
        if(c[i][m - 1] == '1')mx = min(mx, cnt);
    }
    for(int j = 0; j < m; j++) {
        int cnt = 0;
        for(int i = 1; i <= n; i++) {
            if(c[i][j] == '1')cnt ++;
            else if(j > 0 && c[i - 1][j] == '1' && c[i][j] == '0') {
                mx1 = min(mx1, cnt);
                cnt = 0;
            }
        }
        if(c[n][j] == '1')mx1 = min(mx1, cnt);
    }
    for(int i=1;i<=2500;i++){
        if(i > mx1)break;
        for(int j=1;j<=i;j++){
            if(i%j==0){
                if((i / j) > mx)continue;
                v[i].push_back({j,i/j});
            }
        }
    }
    int ans=1;
    for(int i=2;i<=n*m;i++){
        if(ch(i)==1){
            ans=i;
        }
    }
    cout<<ans;
}

Compilation message (stderr)

bomb.cpp: In function 'int main()':
bomb.cpp:59:8: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   59 | freopen("input.txt", "r", stdin);
      | ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
bomb.cpp:60:8: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   60 | freopen("output.txt", "w", stdout);
      | ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 100