Cod sursa(job #2508499)
Utilizator | Data | 12 decembrie 2019 13:00:40 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 30 |
Compilator | cpp-64 | Status | done |
Runda | Arhiva educationala | Marime | 0.37 kb |
#include<bits/stdc++.h>
using namespace std;
ifstream fin("ciur.in");
ofstream fout("ciur.out");
int n,i,j,nr,v[200001];
int main()
{ fin>>n;
for( i=2;i*i<=n;i++){
if(v[i]==0){
for(j=2;i*j<=n;j++)
v[i*j]=1;
}
}
for (i=2;i<=n;i++)
if(v[i]==0)
nr++;
fout<<nr;
return 0;
}