POJ 3624 Charm Bracelet

#include<stdio.h>
#include<string.h>
#include<math.h>
#include<iostream>
#include<algorithm>
#include<queue>
#include<stack>
#define mem(a,b) memset(a,b,sizeof(a))
#define ll __int64
#define MAXN 1000
#define INF 0x7ffffff
#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1
using namespace std;

int dp[13880];
int main()
{
    int n,m;
    int i,j;
    int w,d;
    int maxx;
    while(scanf("%d%d",&n,&m)!=EOF)
    {
        mem(dp,-1);
        dp[0]=0;maxx=0;
        while(n--)
        {
            scanf("%d%d",&w,&d);
            for(i=m;i>=w;i--)
            {
                if(dp[i-w]!=-1&&dp[i-w]+d>dp[i])
                {
                    dp[i]=dp[i-w]+d;
                    if(dp[i]>maxx) maxx=dp[i];
                }
            }
        }      
        printf("%d\n",maxx);
    }
    return 0;
}