Cod sursa(job #248635)
| Utilizator | Data | 26 ianuarie 2009 12:52:16 | |
|---|---|---|---|
| Problema | Ciurul lui Eratosthenes | Scor | 0 |
| Compilator | cpp | Status | done |
| Runda | Arhiva educationala | Marime | 0.27 kb |
#include<fstream.h>
ifstream f("data.in");
ofstream g("data.out");
int main()
{unsigned long N,i,j,a[20000],x=0;
f>>N;
for(i=1;i<=N;i++)
a[i]=1;
for(i=2;i<=N;i++)
if(a[i]==1)
x++
for(j=i+i;j<=N;j=j+i)
a[j]=0;
g<<x;
f.close();g.close();
return 0;}