백준 11648 자바 - 지속

// 지속
package Bronze_III_3;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Ex11648 {
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        int n = Integer.parseInt(br.readLine());
        int cnt = 0;

        while (n >= 10) {
            int mul = 1;

            while (n > 0) {
                mul *= n % 10;
                n /= 10;
            }
            n = mul;
            cnt++;
        }
        System.out.println(cnt);
    }
}