HDU 2746 ——Max Sum Plus Plus Plus

#include <cstdio>
#include <iostream>
#include <cstring>
#include <string>
#define INF 0x3f3f3f3f
using namespace std;

int a[1005];
int sum[1005];
int l[25];
int dp[25][1005];
int n, m;

int dfs(int i, int cur)
{    
    if(cur > n)    return -INF;
    
    if(i==m+1)    return 0;
    
    if(dp[i][cur])    return dp[i][cur];
    
    int ret=-INF;
    for(int k=cur; k<n; k++) {
        ret = max(ret, dfs(i+1, k+l[i])+sum[k+l[i]]-sum[k]);
    }
    return dp[i][cur] = ret;
}

int main ()
{
    while(scanf("%d", &n) != EOF && n) {
        scanf("%d", &m);
        for(int i=1; i<=m; i++) {
            scanf("%d", &l[i]);
        }
        for(int i=1; i<=n; i++) {
            scanf("%d", &a[i]);
            sum[i] = sum[i-1] + a[i];
        }
        printf("%d\n", dfs(1, 0));
        memset(dp, 0, sizeof(dp));
    }
        
    return 0;
}