检查数字是否可以被JS中的另一个数字整除

Question

I am pretty new at this stuff, and I am solving a series of questions, but I've got lost in this one.

I have to verify if a number can be divided by other, and the answer must be true or false.

I got his

function solucao(numero, x) {
    
    solucao(numero % x); 
    
    if (solucao === 0)  {
        resultado = true;
        
    }else{
        resultado = false;
    }
            
}

But I'm getting runtime error and can't see whats is missing.

Answer 1

So you want to check if a number numero is divisible by x . The modulo operator can help. Try this:

function solucao(numero, x){
    if (numero % x == 0){
        return true
    }
    else {
        return false
    }
}

Answer 2

function solucao(numero, x) {
    
    let resultado;
    
    if (numero % x === 0)  {
        resultado = true;
        
    }else{
        resultado = false;
    }
            return resultado;
}

I think you get confused at some point. You are calling the function, inside of itself. You should do like this, and also, declare the result variable.

Answer 3

I am sure this will help:

    function checkIfDivided(){
// in this section the variables come from an html document
            var number=parseInt(document.getElementById("number").value);
             var divisor=parseInt(document.getElementById("divisor").value);
            if(number%divisor==0)
              return true;
            else return false;
    }


or



    function checkIfDivided(number,divisor){
//in the function the variable are given as parameters
            if(number%divisor==0)
              return true;
            else return false;

    }

Answer 4

Looks like two things to me:

1. You haven't declared your 'resultado' variable ( this can be as simple as just typing 'let resultado;' without the single quotes

2. You haven't returned your 'resultado' variable after the if/else statement

Right now, your function is using an undeclared variable and not returning anything, so that is why you are getting an error. Fix the two above steps and you should be good: :)

Answer 5

You clearly understand that the modulus operator is the way to go. Using it we discover that 12 is divisible by 3 because 12 % 3 return zero. Zero is considered a "falsy" value while any other number is considered "truthy".

Given this then if 12 % 3 returns a "falsey" value (zero) we can't use the result directly. But what if we can "flip" false to true? We can, using the not operator ( ! ).

Using the ! operator on the result of a math problem requires the use of parentheses around the math problem itself.

So the problem in code becomes (12 % 3) and to 'flip' it with the ! operator it becomes

!(12 % 3) .

This is proven below with:

1. console.log(!(12 % 3)) --> logs true
2. console.log(!(12 % 5)) --> logs false

The function implementation of that is simple and also proven:

1. console.log(isDivisible(12,3)); --> logs true
2. console.log(isDivisible(12,5)); --> logs false

 console.log(.(12 % 3)) console,log(;(12 % 5)) function isDivisible(number. x){ return,(number % x); } console.log(isDivisible(12,3)); console.log(isDivisible(12,5));

Answer 6

There is one other way to do so and i think its much cleaner.

console.log(Number.isInteger(10/2)) //true
console.log(Number.isInteger(4/2)) // false

//a must be greater than b
function check(a,b) {
 console.log(Number.isInteger(a/b))
 return Number.isInteger(a/b)
}

check(10,5)//true
check(8,3)//false