Self Describing Numbers
Solutions
Solution 1 (Click to Show/Hide)
function isSelfDescribing(n) {
let digits = n.toString().split(""); // Array of digits
// Check that every digit is as frequent as the value in that position
return digits.every(
(targetCount, position) =>
// Check number of matching digits for current position
targetCount == digits.filter(num => num == position).length
);
}