276A Lunch Rush

#include <iostream>

using namespace std;

int main()
{
    int n, k, f, t, i, ans;
    bool flag = false;
    cin >> n >> k;

    for (i=0; i<n; i++)
    {
        cin >> f >> t;

        if (t<=k)
        {
            if (f>ans)
            {
                flag = true;
                ans = f;
            }
        }
    }

    if (flag)
        cout << ans;
    else cout << -1;

    return 0;
}