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) // => falseisSquare( 3) // => falseisSquare( 4) // => trueisSquare(25) // => trueisSquare(26) // => false

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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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