2015弱校联盟(1) -A. Easy Math

A. Easy Math
Time Limit: 2000ms
Memory Limit: 65536KB

Given n integers a1,a2,…,an, check if the sum of their square root a1−−√+a2−−√+⋯+an−−√ is a integer.
Input
The input consists of multiple tests. For each test:

The first line contains 1 integer n (1≤n≤105).
The second line contains n integers a1,a2,…,an (0≤ai≤109).

Output
For each test, write ‘‘Yes′′ if the sum is a integer, or ‘‘No′′ otherwise.

Sample Input

2
1 4
2
2 3

Sample Output

Yes
No
判断每一个数是不是平方数,如果不是平方数,最后的结果不是整数

#include <bits/stdc++.h>
#define LL long long
#define fread() freopen("in.in","r",stdin)
#define fwrite() freopen("out.out","w",stdout)

using namespace std;


int main()
{
    int n,data;
    while(~scanf("%d",&n))
    {
        bool flag=false;
        while(n--)
        {
            scanf("%d",&data);
            if(flag)
            {
                continue;
            }
            int ans=(int)sqrt(data);
            if(ans*ans!=data)//判断是不是平方数
            {
                flag=true;
            }
        }
        if(flag)
        {
            cout<<"No"<<endl;
        }
        else
        {
            cout<<"Yes"<<endl;
        }
    }
    return 0;
}