Cod sursa(job #1932639)
Utilizator | Data | 19 martie 2017 22:29:58 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.21 kb |
#include<fstream>
using namespace std;ifstream fin("ciur.in");ofstream fout("ciur.out");int n,i,j,nr;char p[2000011];int main(){fin>>n;for(i=2; i<=n; i++)if(!p[i]){nr++;for(j=i+i; j<=n; j+=i) p[j]=1;}fout<<nr<<'\n';}