java 獲取一個數字中，各個數字出現的次數

 

//find number of times each digit occur in a number
import java.util.Scanner;

public class Numbers {

    public static void main(String[] args) {
        int num;
        int[] arr = new int[10]; // we use hashing to solve this problem
        Scanner ip = new Scanner(System.in);
        System.out.print("Enter a number: ");
        num = ip.nextInt();
        while (num > 0) {
            int rem = num % 10;
            arr[rem]++; // increment the values in array.
            num = num / 10;
        }
        for (int i = 0; i <= 9; i++) {
            if (arr[i] > 0)
                System.out.println(i + ": " + arr[i] + " times");
        }
        ip.close();
    }
}


OUTPUT:
Enter a number: 12345221
1: 2 times
2: 3 times
3: 1 times
4: 1 times
5: 1 times