Cod sursa(job #290219)
Utilizator | Data | 27 martie 2009 17:25:04 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 20 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.21 kb |
#include<fstream.h>
int p[2001],N,i=2,n,j;
int main()
{ifstream f("ciur.in");
ofstream g("ciur.out");
f>>N;
for(i=2;i<=N;++i)
if(!p[i])
{for(j=2*i;j<=N;j+=i)
p[j]=1;
++n;
}
g<<n;
return 0;
}