P2380 狗哥采矿

#include<iostream>
#include<algorithm>
#include<cstring>
const int maxn=1010;
using namespace std;
int n,m;
int dp[maxn][maxn];
int a[maxn][maxn];
int b[maxn][maxn];
int sum1[maxn][maxn];
int sum2[maxn][maxn];
int main()
{
    cin>>n>>m;
    while(m!=0||n!=0)
    {
        memset(a,0,sizeof(a));
        memset(b,0,sizeof(b));
        memset(sum1,0,sizeof(sum1));
        memset(sum2,0,sizeof(sum2));
        memset(dp,0,sizeof(dp));
        for(int i=1;i<=n;i++)
        {
            for(int j=1;j<=m;j++)
            {
                cin>>b[i][j];
                sum1[i][j]=sum1[i][j-1]+b[i][j];
            }
        }
        for(int i=1;i<=n;i++)
        {
            for(int j=1;j<=m;j++)
            {
                cin>>a[i][j];
                sum2[i][j]=sum2[i-1][j]+a[i][j];
            }
        }
        for(int i=n;i>=0;i--)
        {
            for(int j=m;j>=0;j--)
            {
                    dp[i][j]=max(dp[i][j+1]+sum2[i][j+1],dp[i+1][j]+sum1[i+1][j]);
            }
        }
        cout<<dp[0][0]<<endl;
        cin>>n>>m;
    }
    return 0;
 }