Luogu P2370 yyy2015c01的U盘

Code

#include<cstdio>
#include<cstring>
#include<algorithm>
#define N 1010
#define W 1010
using namespace std;
int dp[W],v[N],w[N],n,m,p;
bool Check(int x)
{
    memset(dp,0,sizeof(dp));
    for (int i = 1;i <= n;++i)
    {
        if (w[i] > x) continue ; 
        for (int j = m;j >= w[i];--j)
            dp[j] = max(dp[j],dp[j - w[i]] + v[i]);
    }
    if(dp[m] < p) return 0;
    return 1;
}
void solve()
{
    int lb = 0,ub = m;
    while(lb + 1 < ub){
        int mid = (lb + ub)/2;
        //mid should be smaller 
        if(Check(mid)) ub = mid;
        else lb = mid;
    }
    if(ub == m) printf("No Solution!");
	else printf("%d",ub);
}
int main()
{
    scanf("%d%d%d",&n,&p,&m);
    for(int i = 1;i <= n;++i){
        scanf("%d%d",&w[i],&v[i]);
    }
    solve();
    return 0;
}