public class RecursionDemo2
1:
2: import java.util.*;
3:
4: public class RecursionDemo2
5: {
6: public static void main(String[] args)
7: {
8: System.out.println("Enter a nonnegative number:");
9: Scanner keyboard = new Scanner(System.in);
10: int number = keyboard.nextInt( );
11: System.out.println(number + " contains "
12: + numberOfZeros(number) + " zeros.");
13: }
14:
15: /**
16: Precondition: n >= 0
17: Returns the number of zero digits in n.
18: */
19: public static int numberOfZeros(int n)
20: {
21: if (n == 0)
22: return 1;
23: else if (n < 10)//and not 0
24: return 0;//0 for no zeros
25: else if (n%10 == 0)
26: return(numberOfZeros(n/10) + 1);
27: else //n%10 != 0
28: return(numberOfZeros(n/10));
29: }
30: }
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35:
36: