function addTrailingZeros(num : number, len : number) : string {
return String(num).padEnd(len, '0');
}
console.log(addTrailingZeros(3.1, 4));
console.log(addTrailingZeros(2.2, 5));
console.log(addTrailingZeros(7.4, 6));
console.log(addTrailingZeros(-7.4, 6));
/*
run:
"3.10"
"2.200"
"7.4000"
"-7.400"
*/