- Perfect Number
We define the Perfect Number is a positive integer that is equal to the sum of all its positive divisors except itself.
Now, given an integer n, write a function that returns true when it is a perfect number and false when it is not.
这道题其实很简单,直接按照题目给的意思做就好了。
代码如下:
class Solution {
public:
bool checkPerfectNumber(int num) {
int sum=1;
if(num==1)return false;
else {
for(int i=2;i<=sqrt(num);i++){
if(num%i==0){
sum+=i;
sum+=num/i;
}
}
if(sum==num)return true;
else return false;
}
}
};