foj2013

//Problem 2013 A short problem 
/*Accept: 158    Submit: 452
Time Limit: 1000 mSec    Memory Limit : 32768 KB
 Problem Description
The description of this problem is very short. Now give you a string(length N), and ask you the max sum of the substring which the length can't small than M.
Input
The first line is one integer T(T≤20) indicates the number of the test cases. Then for every case, the first line is two integer N(1≤N≤1000000) and M(1≤M≤N).
Then one line contains N integer indicate the number. All the number is between -10000 and 10000.
Output
Output one line with an integer.
Sample Input
2
5 1
1 -2 -2 -2 1
5 2
1 -2 -2 -2 1
 Sample Output
1
-1
*/
#include"iostream"
using namespace std;
const int M=1000005;
int t,n,m;
int i,j;
int a[M];
int sum[M];
int f[M];
int cmp(int a,int b)
{
      return a>b?a:b;
}
int main()
{
    scanf("%d",&t);
    while(t--)
    {
        scanf("%d %d",&n,&m);
        for(i=1;i<=n;i++) scanf("%d",&a[i]);
        int i,Max=-0x7fffffff;
        sum[0]=0;
        for(i=1;i<=n;i++)  sum[i]=sum[i-1]+a[i];
        f[m-1]=sum[m-1];
        
        for(i=m; i<=n; i++) 
        {
          f[i]=cmp( f[i-1]+a[i],  sum[i]-sum[i-m]);
            if(f[i]>Max) Max=f[i];
        }
        printf("%d\n",Max);
    }
    return 0;
}