function addTrailingZeros(num, len) {
return String(num).padEnd(len, '0');
}
console.log(addTrailingZeros(4.1, 4));
console.log(addTrailingZeros(5.2, 5));
console.log(addTrailingZeros(2.4, 6));
console.log(addTrailingZeros(-2.4, 6));
/*
run:
"4.10"
"5.200"
"2.4000"
"-2.400"
*/