Cod sursa(job #1769467)
Utilizator | Papa Valentin papinub2 | Data | 2 octombrie 2016 16:16:32 |
---|---|---|---|
Problema | Factorial | Scor | 15 |
Compilator | cpp | Status | done |
Runda | Arhiva de probleme | Marime | 0.53 kb |
#include <fstream>
using namespace std;
ifstream in("fact.in");
ofstream out("fact.out");
long long rez(int x)
{
long long nr=0;
while (x>=5)
{
nr=nr+x/5;
x=x/5;
}
return nr;
}
int main ()
{
int n, k=0, x;
in>>n;
if (n==0)
out<<1;
if (rez(n*5)==n)
out<<n*5;
else
{
while (rez(n*5-k)>=n)
k=k+5;
if (rez(n*5-k) == n)
out<<n*5-k;
else
out<<-1;
}
return 0;
}