“Мутации” Ответ

Мутации

// Mutations
// Return true if the string in the first element of the array contains all
// of the letters of the string in the second element of the array.
//For example, ["hello", "Hello"], should return true because all of the letters
// in the second string are present in the first, ignoring case.

function mutation(arr) {
	let second = arr[1].toLowerCase();
	let first = arr[0].toLowerCase();
	for (let i = 0; i < second.length; i++) {
		if (first.indexOf(second[i]) < 0) return false;
	}
	return true;
}

mutation(['floor', 'FLOOR']);

// OR

function mutation(arr) {
	return arr[1]
		.toLowerCase()
		.split('')
		.every(function (letter) {
			return arr[0].toLowerCase().indexOf(letter) != -1;
		});
}