Cod sursa(job #1033619)
Utilizator | Data | 17 noiembrie 2013 12:46:06 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 90 |
Compilator | cpp | Status | done |
Runda | cei_mici3 | Marime | 0.29 kb |
#include <fstream>
using namespace std;
ifstream f("ciur.in");
ofstream g("ciur.out");
long long i,j,n,nr;
char v[2000000];
int main()
{
f>>n;
for(i=2;i<=n;i++)
v[i]=1;
for(i=2;i<=n;i++)
if(v[i]==1)
{nr++;
for(j=2*i;j<=n;j=j+i)
v[j]=0;
}
g<<nr;
return 0;
}