Cod sursa(job #3141340)
Utilizator | Munteanu Mihnea Gabriel InformaticianInDevenire1 | Data | 13 iulie 2023 18:02:57 |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 20 |
Compilator | cpp-64 | Status | done |
Runda | Arhiva educationala | Marime | 0.63 kb |
#include <bits/stdc++.h>
using namespace std;
ifstream fin ("ciur.in");
ofstream fout ("ciur.out");
int IsPrime [1500];
vector <int> v;
void Ciur(){
IsPrime[0] = 0;
IsPrime[1] = 0;
for (int i=2;i<=1500;++i){
IsPrime[i] = 1;
}
for (int i=2;i<=1500;++i){
for (int j=2*i;j<=1500;j+=i){
IsPrime[j] = 0;
}
}
for (int i=2;i<1500;++i){
if (IsPrime[i]==1){
v.push_back(i);
}
}
}
int main()
{
Ciur();
int n;
fin >> n;
int i = 0;
while(v[i]<=n){
i += 1;
}
fout << i;
return 0;
}