#include <iostream>

using namespace std;

const int MAXN = 1e5 + 5;

int k[MAXN],p[MAXN];
int n,R;
int ans = 0;

int main(){
	cin >> n >> R;
	for (int i=1;i<=n;i++)
		cin >> k[i] >> p[i];
		
	for (int i=1;i<=n;i++)
		if (R >= p[i])
			ans = max(ans, k[i]);
	
	cout << ans << endl;
}