51Nod 1083 矩阵取数问题 | 动态规划

#include "bits/stdc++.h"
using namespace std;
#define LL long long
#define INF 0x3f3f3f3f3f
#define PI acos(-1)
#define N 510
#define MOD 10
using namespace std;
int arr[N+][N+],dp[N+][N+];

int main()
{
    int n;
    while(~scanf("%d",&n)){
        for(int i=;i<=n;i++){
            for(int j=;j<=n;j++){
                scanf("%d",&arr[i][j]);
            }
        }
        for(int i=;i<=n;i++)
            dp[][i]=-INF,dp[i][]=-INF;
        dp[][]=arr[][];
        for(int i=;i<=n;i++){
            for(int j=;j<=n;j++){
                if(i==&&j==)
                    continue;
                dp[i][j]=max(dp[i-][j],dp[i][j-])+arr[i][j];
            }
        }
        printf("%d\n",dp[n][n]);
    }
    return ;
}