HDU-1024 Max Sum Plus Plus 动态规划

代码如下：

#include <cstdio>

#include <cstdlib>

#include <cmath>

#include <cstring>

#include <iostream>

#include <algorithm>

#define MAXN 1000005

using namespace std;



int M, N, seq[MAXN];



int pre[MAXN], cur[MAXN];



int DP()

{

    int Max;

    memset(pre, 0, sizeof (pre));

    memset(cur, 0, sizeof (cur));

    for (int i = 1; i <= M; ++i) { 

        Max = 0x7fffffff+1;

        for (int j = i; j <= N; ++j) {

            cur[j] = max(cur[j-1], pre[j-1]) + seq[j];

            pre[j-1] = Max;   // pre 并不是保留到第j为截止（保留第j个数）的最优值 

            Max = max(Max, cur[j]);

        } 

    }

    return Max;

}



int main()

{

    while (scanf("%d %d", &M, &N) != EOF) {

        for (int i = 1; i <= N; ++i) {

            scanf("%d", &seq[i]);

        }

        printf("%d\n", DP());

    }

    return 0;

}