#include <bits/stdc++.h>   void reduce(unsigned& nom, unsigned& denom) {     bool reduced = true;     while (reduced) {       reduced = false;       for (unsigned i = 2; !reduced && i < 1000; ++i) {         if (nom % i == 0 && denom % i == 0) {           nom /= i;           denom /= i;           reduced = true;         }       }     }   }   void solve() {     unsigned sum = 0;     unsigned A;     std::cin >> A;     for (unsigned i = 2; i < A; ++i) {       auto val = A;       while (val > 0) {         sum += val % i;         val /= i;       }     }     auto nom = sum;     auto denom = A - 2;     reduce(nom, denom);     std::cout << nom <<  /  << denom << std::endl;   }   int main(int argc, char* argv[]) {     { solve(); }     return 0;   }   