**Physical Address**

304 North Cardinal St.

Dorchester Center, MA 02124

Given a **positive** integer *num*, write a function which returns True if *num* is a perfect square else False.

**Follow up:** **Do not** use any built-in library function such as `sqrt`

.

**Example 1:**

```
Input: num = 16
Output: true
```

**Example 2:**

```
Input: num = 14
Output: false
```

**Constraints:**

`1 <= num <= 2^31 - 1`

```
def BitwiseTrick(self, num):
root = 0
bit = 1 << 15
while bit > 0 :
root |= bit
if root > num // root:
root ^= bit
bit >>= 1
return root * root == num
```

```
class Solution {
public:
bool isPerfectSquare(int num) {
int a=1;
while(num>0){
num-=a;
a+=2;
}
return(num==0);
}
};
```

```
class Solution {
public boolean isPerfectSquare(int num) {
long left = 1, right = num;
while (left <= right) {
long mid = (left + right) / 2;
if (mid * mid == num) return true; // check if mid is perfect square
if (mid * mid < num) { // mid is small -> go right to increase mid
left = mid + 1;
} else {
right = mid - 1; // mid is large -> to left to decrease mid
}
}
return false;
}
}
```

In our experience, we suggest you solve this Valid Perfect Square LeetCode Solution and gain some new skills from Professionals completely free and we assure you will be worth it.

If you are stuck anywhere between any coding problem, just visit Queslers to get the Valid Perfect Square LeetCode Solution

I hope this Valid Perfect Square LeetCode Solution would be useful for you to learn something new from this problem. If it helped you then don’t forget to bookmark our site for more Coding Solutions.

This Problem is intended for audiences of all experiences who are interested in learning about Data Science in a business context; there are no prerequisites.

Keep Learning!

**More Coding Solutions >>**