#include <bits/stdc++.h>
using namespace std;

int main() {
  int n,m;
  cin >> n >> m;
  double ans=0;
  while(n--) {
    double x,y;
    cin >> x >> y;
    ans=max(ans,y/x);
  }
  printf("%.10f\n",ans*m);
  return 0;
}
