hdu acmsteps 2.1.2 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): 5139 Accepted Submission(s): 1684

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

#include<iostream>
#include<cmath>
using namespace std;
bool isPrime(int n){
    int sqt=sqrt(n*1.0);
    for(int i=2;i<=sqt;i++)
        if(n%i==0)
            return false;
    return true;
}
int main(){
    //freopen("in.txt","r",stdin);
    for(int n;cin>>n;){
        int num=0,temp;
        while(n--){
            cin>>temp;
            num+=isPrime(temp);
        }
        cout<<num<<'\n';
    }
}

判断素数；