hdu 1024 DP

#include <iostream>
using namespace std;

const int MAXN = 1000010;
__int64 dp[MAXN][2];
int n, m;
__int64 array[MAXN];

inline __int64 MAX(__int64 a, __int64 b)
{
    return a > b ? a : b;
}

int main()
{
    while (scanf("%d %d", &m, &n) != EOF)
    {
        int i, j;
        for (i = 1; i <= n; ++i)
        {
            scanf("%I64d", &array[i]);
        }
        m = m > n ? n : m;

　　　for (i = 0; i <= n; ++i)
        {
            dp[i][0] = 0;
        }
        __int64 _max;
        for (i = 1; i <= m; ++i)        

        {//dp[i][k] = max(dp[i-1][k], max{dp[j][k-1]|(k-1<=j<i)}) + array[i]
            dp[i][1] = dp[i-1][0] + array[i]; 

            _max = dp[i][1];
            for (j = i+1; j <= n-m+i; ++j)
            {
                dp[j][1] = MAX(dp[j-1][1], dp[j-1][0]) + array[j];
                dp[j-1][0] = _max;
                _max = MAX(_max, dp[j][1]);
            }
            dp[j-1][0] = _max;
        }
        printf("%I64d\n", dp[n][0]);
    }
   
    return 0;
}