#include <cstdio>
#include <cmath>
using namespace std;

const double PI=(2*acos(0));
struct R { int n,d; };
double d;

R solve(R m, R l, R r) {
  if (fabs((double)m.n/m.d-PI)<d) return m;
  if ((double)m.n/m.d-PI>0) return solve((R){m.n+l.n,m.d+l.d},l,m);
  else return solve((R){m.n+r.n,m.d+r.d},m,r);
}


int main() {
  while(scanf("%lf",&d),fabs(d)>1e-8) {
    R res=solve((R){1,1},(R){0,1},(R){1,0});
    printf("%d/%d\n",res.n,res.d);
  }
}