FZU 2214 Knapsack dp (转化背包)

#include<cstdio>
#include<cstring>
#include<algorithm>
#include<iostream>
#include<cstdlib>
#include<cmath>
#include<cstdlib>
#include<vector>
#include<queue>
using namespace std;
typedef long long LL;
const int INF=0x3f3f3f3f;
const int maxn=5005;
LL dp[maxn];
int w[505],v[505];
int main()
{
    int T;
    scanf("%d",&T);
    while(T--)
    {
        int n,b;
        scanf("%d%d",&n,&b);
        memset(dp,INF,sizeof(dp));
        int sum=0;
        for(int i=1;i<=n;++i)
            scanf("%d%d",&w[i],&v[i]),sum+=v[i];
        dp[0]=0;
        for(int i=1;i<=n;++i)
        {
           for(int j=sum;j>=v[i];--j)
            if(dp[j-v[i]]!=INF)
            dp[j]=min(dp[j-v[i]]+w[i],dp[j]);
        }
        int ans=0;
        for(int i=sum;i>0;--i)
          if(dp[i]!=INF&&dp[i]<=b)ans=max(ans,i);
          printf("%d\n",ans);
    }
    return 0;
}