function isPrime(n: number): boolean {
if (n < 2) return false;
if (n % 2 === 0) return n === 2;
const limit: number = Math.floor(Math.sqrt(n));
for (let i = 3; i <= limit; i += 2) {
if (n % i === 0) return false;
}
return true;
}
function hasUniqueDigits(n: number): boolean {
const digits: string = n.toString();
const unique: Set<string> = new Set(digits);
return unique.size === digits.length;
}
function main(): void {
for (let num = 1000; num <= 9999; num++) {
if (isPrime(num) && hasUniqueDigits(num)) {
console.log(`First 4-digit prime with all unique digits: ${num}`);
return; // stop after finding the first one
}
}
console.log("No such number found.");
}
main();
/*
run:
"First 4-digit prime with all unique digits: 1039"
*/
