EN
JavaScript - check if number is odd in Vanilla JS
3
points
In this short article we will show you how in JavaScript check if number is odd.
Odd integer numbers are:
... -7 -5 -3 -1 1 3 5 7 ...Simple test example:
// ONLINE-RUNNER:browser;
function isOdd(number) {
return number % 2 !== 0;
}
console.log( isOdd(0) ); // false
console.log( isOdd(1) ); // true <------ odd
console.log( isOdd(2) ); // false
console.log( isOdd(3) ); // true <------ odd
console.log( isOdd(4) ); // false
console.log( isOdd(5) ); // true <------ odd
console.log( isOdd(-1) ); // true <------ odd
console.log( isOdd(-2) ); // false
console.log( isOdd(-3) ); // true <------ odd
console.log( isOdd(-4) ); // false
console.log( isOdd(-5) ); // true <------ oddAlternative solution 1 - negative numbers conversion:
// ONLINE-RUNNER:browser;
function isOdd(number) {
if (number < 0) {
number = -number;;
}
return number % 2 === 1;
}
console.log( isOdd(0) ); // false
console.log( isOdd(1) ); // true <------ odd
console.log( isOdd(2) ); // false
console.log( isOdd(3) ); // true <------ odd
console.log( isOdd(4) ); // false
console.log( isOdd(5) ); // true <------ odd
console.log( isOdd(-1) ); // true <------ odd
console.log( isOdd(-2) ); // false
console.log( isOdd(-3) ); // true <------ odd
console.log( isOdd(-4) ); // false
console.log( isOdd(-5) ); // true <------ oddAlternative solution 2 - bitwise operator:
// ONLINE-RUNNER:browser;
function isOdd(number) {
return (number & 1) > 0;
}
console.log( isOdd(0) ); // false
console.log( isOdd(1) ); // true <------ odd
console.log( isOdd(2) ); // false
console.log( isOdd(3) ); // true <------ odd
console.log( isOdd(4) ); // false
console.log( isOdd(5) ); // true <------ odd
console.log( isOdd(-1) ); // true <------ odd
console.log( isOdd(-2) ); // false
console.log( isOdd(-3) ); // true <------ odd
console.log( isOdd(-4) ); // false
console.log( isOdd(-5) ); // true <------ oddÂ