Cod sursa(job #361383)
Utilizator | Data | 4 noiembrie 2009 21:06:27 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 30 |
Compilator | cpp | Status | done |
Runda | CNRV #4 | Marime | 0.32 kb |
#include <fstream>
#include <iostream>
using namespace std;
int v[2000001];
int main(){
int i,j,n,d=0;
ifstream f("ciur.in");
ofstream g("ciur.out");
f>>n;
for(i=2;i<=n;i++)v[i]=1;
for(i=2;i<=n;i++)if(v[i]){
d++;
for(j=i+i;j<=n;j=j+i)
v[j]=0;
}
g<<d;
return 0;
}