#include <bits/stdc++.h>
using namespace std;
template <class T>
inline T sqr(T x) {
  return x * x;
}
template <class T>
inline T gcd(T a, T b) {
  if (a < 0) return gcd(-a, b);
  if (b < 0) return gcd(a, -b);
  return (b == 0) ? a : gcd(b, a % b);
}
template <class T>
inline T absval(T a) {
  if (a < 0)
    return -a;
  else
    return a;
}
int toInt(string s) {
  istringstream iss(s);
  int res;
  if (!(iss >> res)) res = -1;
  return res;
}
string toString(int a) {
  ostringstream oss;
  oss << a;
  return oss.str();
}
vector<string> getTokens(string s, char delim) {
  vector<string> tokens;
  istringstream iss(s);
  string temp;
  while (getline(iss, temp, delim)) {
    tokens.push_back(temp);
  }
  return tokens;
}
const int MaxMatrixSize = 1000;
template <class T>
inline void printMat(int n, T A[MaxMatrixSize][MaxMatrixSize]) {
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < n; j++) cout << A[i][j] << " ";
    cout << endl;
  }
}
template <class T>
inline void printVec(vector<T> A) {
  for (int i = 0; i < A.size(); i++) {
    cout << A[i] << " ";
  }
}
double dist(double x1, double y1, double x2, double y2) {
  return sqrt(sqr(x1 - x2) + sqr(y1 - y2));
}
double distR(double x1, double y1, double x2, double y2) {
  return sqr(x1 - x2) + sqr(y1 - y2);
}
class Compare {
 public:
  bool operator()(pair<int, int> i, pair<int, int> j) {
    if (i.second < j.second)
      return true;
    else
      return false;
  }
} comp;
class Codeforces {
 public:
  int task(vector<pair<int, int> > a, int n, int s) {
    (sort(a.begin(), a.end(), comp));
    int maxi = -1;
    for (int i = (0); i < (n); i++) {
      if (a[i].first < s) {
        if (a[i].second == 0)
          maxi = 0;
        else {
          maxi = (100 - a[i].second);
          break;
        }
      } else if (a[i].first == s && a[i].second == 0) {
        maxi = 0;
      }
    }
    return maxi;
  }
};
int main() {
  Codeforces cf = Codeforces();
  int n, s;
  scanf("%d %d", &n, &s);
  vector<pair<int, int> > a;
  a.resize(n);
  for (int i = (0); i < (n); i++) {
    scanf("%d %d", &a[i].first, &a[i].second);
  }
  printf("%d\n", cf.task(a, n, s));
  return 0;
}
