0分求调

Tim_justforsure @ 2023-07-14 15:06:32

#include<iostream>
using namespace std;
const int N=1e3+5;
int n,m;
int sum[N][N],a[N][N];
int main(){
    cin>>n;
    for (int i=1;i<=n;i++){
        for (int j=1;j<=n;j++){
            cin>>a[i][j];
            sum[i][j]=sum[i-1][j]+sum[i][j-1]-sum[i-1][j-1]+a[i][j];
        }
    }
    int ans=0;
    for (int x1=1;x1<=n;x1++){
        for (int y1=1;y1<=n;y1++){
            for (int x2=x1;x2<=n;x2++){
                for (int y2=y1;y2<=n;y2++){
                    ans=max(ans,sum[x2][y2]-sum[x1-1][y2]+sum[x1-1][y1-1]);
                }
            }
        }
    }
    cout<<ans;
    return 0;
}

by RicardoMZhou @ 2023-07-14 15:07:26

6

by FengYuXinMing @ 2023-07-14 15:11:11

@Tim0303 少一步

by RicardoMZhou @ 2023-07-14 15:11:33

#include<iostream>
#define INF 0x3f3f3f3f
using namespace std;
const int N=1e3+5;
int n,m;
int sum[N][N],a[N][N];
int main(){
    cin>>n;
    for (int i=1;i<=n;i++){
        for (int j=1;j<=n;j++){
            cin>>a[i][j];
            sum[i][j]=sum[i-1][j]+sum[i][j-1]-sum[i-1][j-1]+a[i][j];
        }
    }
    int ans=0;
    for (int x1=1;x1<=n;x1++){
        for (int y1=1;y1<=n;y1++){
            for (int x2=x1;x2<=n;x2++){
                for (int y2=y1;y2<=n;y2++){
                   ans=max(ans,sum[x2][y2]-sum[x1-1][y2]-sum[x2][y1-1]+sum[x1-1][y1-1]);
                }
            }
        }
    }
    cout<<ans;
    return 0;
}

by RicardoMZhou @ 2023-07-14 15:12:18

调完了@ Tim0303

by Tim_justforsure @ 2023-07-14 15:13:17

@RicardoMZhou ok

by FengYuXinMing @ 2023-07-14 15:13:36

要在4层循环里面，第二个运算之后加一个-sum x2 y1-1