HDU1024Max Sum Plus Plus（M段最大和）

题意：求一个数组中 M 段的 最大和

没看明白怎么搞得

抽空来看，写的不赖

#include <iostream>
#include <cstring>
#include <algorithm>
#include <cstdio>
using namespace std;
const int INF = 0x3f3f3f3f;
const int N = 1000000 + 10;
int dp[N], num[N], pre[N];
int main()
{
    int m, n;
    while (scanf("%d%d", &m, &n) != EOF)
    {
        for (int i = 1; i <= n; i++)
        {
            scanf("%d", &num[i]);
        }
        memset(pre, 0, sizeof(pre));
        memset(dp, 0, sizeof(dp));
        int ans = -INF, maxn;
        for (int i = 1; i <= m; i++)
        {
            maxn = -INF;
            for (int j = i; j <= n; j++)
            {
                dp[j] = max(dp[j - 1], pre[j - 1]) + num[j];
                pre[j - 1] = maxn;
                maxn = max(maxn, dp[j]);
            }
            //if (ans < maxn)
              //  ans = maxn;
        }
        printf("%d
", maxn);
    }

    return 0;
}