SQUARE Probelm_codewars daily train9/27

questions come from www.codewars.com

You're a square!

A square of squares

You like building blocks. You especially like building blocks that are squares. And what you even like more, is to arrange them into a square of square building blocks!

However, sometimes, you can't arrange them into a square. Instead, you end up with an ordinary rectangle! Those blasted things! If you just had a way to know, whether you're currently working in vain… Wait! That's it! You just have to check if your number
of building blocks is a perfect square.

Task

Given an integral number, determine if it's a
square number:

In mathematics, a square number or perfect square is an integer that is the square of an integer; in other words, it is the product of some integer with itself.

The tests will always use some integral number, so don't worry about that in dynamic typed languages.

Examples

isSquare(-1) // => false
isSquare( 3) // => false
isSquare( 4) // => true
isSquare(25) // => true
isSquare(26) // => false

solution

var isSquare = function(n){
  var sqrt;
  sqrt = Math.pow(n,1/2);
  
  return isIntegral(sqrt); // fix me
}

function isIntegral(n) {
  return (typeof(n)==="number") && (Math.trunc(n)===n);//or Math. round
}

testcases

Test.describe("isSquare", function(){
  Test.it("should work for some examples", function(){
    Test.expect(!isSquare(-1), "Negative numbers cannot be square numbers");
    Test.expect(!isSquare( 3));
    Test.expect( isSquare( 4));
    Test.expect( isSquare(25));
    Test.expect(!isSquare(26));
  });
  Test.it("should work for random square numbers", function(){
    var r, i;
    for(i = 0; i < 100; ++i){
      r = (Math.random() * 0xfff0) | 0;
      Test.expect(isSquare(r*r), (r * r) + " is a square number");
    }
  });
});

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