POJ_3627 Bookshelf

# include<cstdio>
# include<iostream>
# include<algorithm>

using namespace std;

int cow[20010];

int main(void)
{
    int n;cin>>n;
    int b;cin>>b;
    for ( int i = 0;i < n;i++ )
    {
        cin>>cow[i];
    }
    sort(cow,cow+n);
    int sum = 0;
    int i = n;
    while ( sum < b )
    {
        i--;
        sum+=cow[i];
    }
    cout<<n-i<<endl;

    return 0;
}