Cod sursa(job #687374)
Utilizator | Mustea Iulia-Otilia iuliaotilia26 | Data | 22 februarie 2012 12:52:20 |
---|---|---|---|
Problema | Factorial | Scor | 55 |
Compilator | cpp | Status | done |
Runda | Arhiva de probleme | Marime | 0.53 kb |
#include<fstream>
#include<math.h>
using namespace std;
int main()
{
long long i,p,ok,j,m,pr,k,x,MAX;
ifstream fin("fact.in");
ofstream fout("fact.out");
fin>>p;
MAX=pow(10,8);
if(p==0)fout<<1;
else
{
i=0;j=MAX;ok=0;
while(i<=j&&ok==0)
{
m=(i+j)/2;
pr=5;k=0;
while(pr<m)
{
k=k+m/pr;
pr=pr*5;
}
if(k==p)
{
x=m-m%5;
ok=1;
}
else if(k<p)i=m+1;
else j=m-1;
}}
if(ok==1)fout<<x;
else fout<<"-1";
fin.close();
fout.close();
return 0;
}