Cod sursa(job #1477888)

Utilizator BodStfBodoarca Stefan BodStf Data 27 august 2015 12:24:36
Problema Ciurul lui Eratosthenes Scor 30
Compilator cpp Status done
Runda Arhiva educationala Marime 0.35 kb
Raporteaza aceasta sursa 
#include<stdio.h>
#include<malloc.h>

#define MAX 2000005
int a[MAX];

int main()
{
	FILE* f1,*f2;
	f1=fopen("ciur.in","r");
	f2=fopen("ciur.out","w");
	int N,count=0,i;
	fscanf(f1,"%d",&N);
	for(i=2;i<=N;i++)
	{
		if(a[i]!=-1)
		{
		  count++;
		  for(int j=i+i;j<=N;j+=i)
			 a[j]=-1;
		}
	}
	fprintf(f2,"%d\n",count);
    return 0;
}