hdu 2138

How many prime numbers

Time Limit: 3000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)

Total Submission(s): 7656    Accepted Submission(s): 2563

Problem Description   Give you a lot of positive integers, just to find out how many prime numbers there are.  

Input   There are a lot of cases. In each case, there is an integer N representing the number of integers to find. Each integer won’t exceed 32-bit signed integer, and each of them won’t be less than 2.  

Output   For each case, print the number of prime numbers you have found out.  

Sample Input

3
2 3 4
        

Sample Output

2
        

Author wangye  

Source HDU 2007-11 Programming Contest_WarmUp  

Recommend 威士忌  

#include <stdio.h>
#include <math.h>
int isPrime(int n)
{
	int i, l = sqrt(n);
	for(i = 2; i <= l; i++)
		if(n % i == 0)
			return 0;
	return 1;
}
int main()
{
	int n, num, acount;
	while(~scanf("%d", &n))
	{
		acount = 0;
		while(n--)
		{
			scanf("%d", &num);
			if(isPrime(num))
				acount++;
		}
		printf("%d\n", acount);
	}
	return 0;
}