Cod sursa(job #2178405)

Utilizator RaresMacoveiMacovei Rares-Stefan RaresMacovei Data 19 martie 2018 14:18:21
Problema Factorial Scor 5
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.3 kb
Raporteaza aceasta sursa 
#include <bits/stdc++.h>

using namespace std;

ifstream fin("fact.in");
ofstream fout("fact.out");

int main()
{
    long long p,po=5,s;
    fin>>p;
    if(p%10==5 && p!=0) {fout<<"-1";return 0;}
    s=p*5;
    while(po<=p){
        s-=po;
        po*=5;
    }
    fout<<s;
    return 0;
}