in app/src/app/filters/number.pipe.ts [7:15]
private pad(n: number) {
if (n < 1000 && n >= 100) {
return `${n}`;
} else if (n < 100 && n >= 10) {
return `0${n}`;
} else if (n < 10 && n >= 0) {
return `00${n}`;
}
}