题解 | #最小面积子矩阵#

#include<bits/stdc++.h>
using namespace std;

int main(){
    int n,m,k;
    while(cin>>n>>m>>k){
        vector<vector<int>> s(n+1,vector<int>(m+1,0));vector<vector<int>> a(n+1,vector<int>(m+1,0));
     for(int i=1;i<=n;i++){
         for(int j=1;j<=m;j++){
             cin>>a[i][j];
         }
     }
     for(int i=1;i<=n;i++){
         for(int j=1;j<=m;j++){
            s[i][j]=s[i-1][j]+s[i][j-1]+a[i][j]-s[i-1][j-1];
         }
     }
     int sss=INT_MAX;
     for(int x2=1;x2<=n;x2++){
         for(int y2=1;y2<=m;y2++){
             {
                 for(int x1=x2;x1<=n;x1++){
                     for(int y1=y2;y1<=m;y1++){
                         int ik=s[x1][y1]-s[x2-1][y1]-s[x1][y2-1]+s[x2-1][y2-1];
    if(ik>=k)
    {   
        sss=min(sss,(x1-x2+1)*(y1-y2+1));
    }
                     }
                 }
             }
              
         }
     }
     if(sss==INT_MAX)
     cout<<-1<<endl;
     else
      cout<<sss<<endl;
    
     
        
        
    }
    return 0;
}