#include <bits/stdc++.h>
using namespace std;
const int maxn = 205;
int n, s;
int x[maxn], y[maxn];
int main() {
  scanf("%d%d", &n, &s);
  int ans = -1;
  for (int i = 0; i < n; i++) {
    scanf("%d%d", &x[i], &y[i]);
    if (x[i] < s && y[i] != 0) ans = max(ans, 100 - y[i]);
    if (x[i] < s && y[i] == 0) ans = max(ans, 0);
    if (x[i] == s && y[i] == 0) ans = max(ans, 0);
  }
  printf("%d\n", ans);
}
