function isRepdigitNumber(num: number) {
let str: string = num.toString();
const arr: string[] = [...str];
const st: any = new Set(arr);
return st.size == 1;
}
const num: number = 99999999;
if (isRepdigitNumber(num)) {
console.log("yes");
} else {
console.log("no");
}
/*
run:
"yes"
*/