Cod sursa(job #387639)
Utilizator | Data | 28 ianuarie 2010 08:45:43 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.31 kb |
#include <stdio.h>
FILE*f=fopen("ciur.in","r");
FILE*g=fopen("ciur.out","w");
int n,i,j,v[2000002],x;
char w[2000002];
int main() {
fscanf(f,"%d",&n);
for(i=2;i<=n;i++){
if(w[i]==0){
x++;
for(j=i;j<=n;j+=i)
w[j]=1;
}
}
fprintf(g,"%d",x);
fclose(g);
fclose(f);
return 0;
}