Cod sursa(job #828826)
Utilizator | Data | 4 decembrie 2012 15:19:12 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 40 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.29 kb |
#include <fstream>
using namespace std;
unsigned char a[2000009];
int main()
{
unsigned int m,y,i;
double n;
ifstream f1("ciur.in");
f1>>n;
m=1;
for (y=3;y<=n;y=y+2)
if (!a[y])
{
for (i=y+y;i<=n;i+=y) a[i]=1;
m++;
}
ofstream f2("ciur.out");
f2<<m;
return 0;
}