Question

How to check if the digits of a number are prime in C#

Answer 1

using System;

public class Program
{
	private static bool isPrime(int n) {
		// prime digits = 2, 3, 5, 7

		if (n == 2 || n == 3 || n == 5 || n == 7) {
			return true;
		}

		return false;
	}

	private static bool isDigitsPrime(int n) {
		while (n > 0) {
			if (!isPrime(n % 10)) {
				return false;
			}
			n = n / 10;
		}

		return true;
	}
	public static void Main(string[] args)
	{
		int n = 7355727;

		Console.Write((isDigitsPrime(n) ? "yes" : "no"));
	}
}





/*
run:
     
yes
  
*/

 

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