Cod sursa(job #305838)
| Utilizator |  Sandu Bogdan BooZZy |
Data | 18 aprilie 2009 17:45:38 |
|---|---|---|---|
| Problema | Factorial | Scor | 0 |
| Compilator | cpp | Status | done |
| Runda | Arhiva de probleme | Marime | 0.36 kb |
#include<fstream.h>
long st,dr,p,x,m,n;
long check(long x)
{
long s=0,q=5;
while(q<=x)
{
s+=x/q;
q*=5;
}
return s;
}
int main()
{
ifstream f("fact.in");
ofstream g("fact.out");
f>>p;
st=5;
dr=5000000000;
while(1)
{
m=(st+dr)>>1;
x=check(m);
if(x<p)st=m;
else if(x>p)dr=m;
else {n=m;break;}
}
n=n-n%5;
g<<n;
return 0;
}