Cod sursa(job #362000)
Utilizator | Data | 7 noiembrie 2009 16:06:53 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.32 kb |
#include<fstream>
using namespace std;
int main(){
int n,i,ct=0;
char x[2000001];
ifstream f("ciur.in");
ofstream g("ciur.out");
f>>n;
for(i=2;i<n;i++)
x[i]=1;
for(int d=2;d<=n;d++)
if(x[d]==1){
i=d*2;
ct++;
while(i<n){
x[i]=0;
i=i+d;
}
}
g<<ct;
f.close();
g.close();
}