const numbers = [1, 2, 3, 4, 5] console.log(numbers.indexOf(5)) // -> 4 console.log(numbers.indexOf(0)) // -> -1 console.log(numbers.indexOf(1)) // -> 0 console.log(numbers.indexOf(6)) // -> -1
const numbers = [1, 2, 3, 4, 5] console.log(numbers.indexOf(5)) // -> 4 console.log(numbers.indexOf(0)) // -> -1 console.log(numbers.indexOf(1)) // -> 0 console.log(numbers.indexOf(6)) // -> -1