#include <bits/stdc++.h>
using namespace std;
 
constexpr int MAXN = 1e3 + 7;
int im[MAXN];
 
int main()
{
    int n, k;
    cin >> n >> k;
    pair<int, int> monety[n];
    for(int i = 0; i < n; ++i)
        cin >> monety[i].second >> monety[i].first;
    for(int i = 0; i < n; ++i)
    {
        for(int j = k; j >= monety[i].first; --j)
        {
            if(im[j-monety[i].first])
            {
                im[j] = min(im[j], im[j-monety[i].first] + monety[i].second);
                if(im[j] == 0)
                    im[j] = im[j-monety[i].first] + monety[i].second;
            }
        }
        im[monety[i].first] = monety[i].second;
    }
    if(im[k]) 
        cout << im[k];
    else
        cout << "NIE";
}

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MyAxMAoyIDQKMiA1CjEwIDEz

3 10
2 4
2 5
10 13