Coupons

ACCEPTED in the 5th attempt !! Too many careless errors....
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Question: Coupons
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#include "iostream.h"
#include "math.h"
#include "iomanip.h"

long long int HCF(long long int big, long long int small) {
      if(big % small == 0) return small;
      return HCF(small, big % small);
}

long long int LCM(long long int a, long long int b) {
      return a * b / HCF(a, b);
}

long long int nLCM(int n) {
      if(n == 1) return 1;
      return LCM(n, nLCM(n - 1));
}

int countDigits(long long int n) {
      int i;
      if(!n) return 1;
      for(i = 0; n; i++) n/=10;
      return i;
}

int max(int a, int b) {
      return (a > b)? a : b;
}

int main() {
      int n;
      while(cin >> n) {
              long long int numer = 0;
              long long int denom = nLCM(n);
              for(int k = 1; k <= n; k++) numer += denom / k;
              denom /= n;
              long long int hcf = HCF(numer, denom);
              numer /= hcf;
              denom /= hcf;
              long long int whole = numer / denom;
              numer = numer % denom;
              int wn = countDigits(whole);
              int fn = max(countDigits(numer), countDigits(denom));
              if(numer == 0) cout << whole << endl;
              else {
                      cout << setw(wn + 1) << " " << numer << endl;
                      cout << whole << " " << setw(fn) << setfill('-') << "" << endl;
                      cout << setw(wn + 1) << setfill(' ') << " " << denom << endl;
              }
      }
      return 0;
}
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