HDOJ 2138-How many prime numbers

How many prime numbers

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

Total Submission(s): 14844 Accepted Submission(s): 5140

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

Author

wangye

Source

HDU 2007-11 Programming Contest_WarmUp

#include<stdio.h>
#include<string.h>
#include<cmath>
#include<algorithm>
using namespace std;
bool F(int cmp)
{
    for(int i=2;i<=sqrt(cmp);i++)
    {
        if(cmp%i==0)
        return false;
    }
    return true;
}
int main()
{
    int nn;
    while(scanf("%d",&nn)!=EOF)
    {
        int i,j=0;
        for(i=0;i<nn;i++)
        {
            int yy;
            scanf("%d",&yy);
            if(F(yy))
            j++;
        }
        printf("%d\n",j);
    }
    return 0;
}