A number "n" is given, the task is to print numbers from n to 0 using recursion.
Example: Print numbers from 5 to 0
Input: 5
Output:
5 4 3 2 1 0
Solutions
Method 1: Recursion
We can solve this problem using recursion easily, all we need to do is, "print n" and make a "recursive call with n-1" while "breaking recursion if n < 0" (Base Condition).
package com.cb.recursion;
/*
* Input: 5
* Output: 5,4,3,2,1,0
* */
public class R1_PrintNumbers {
public static void print(int n) {
// base condition
if (n < 0) return;
// work
System.out.println(n);
// recursive call
print(n - 1);
}
public static void main(String[] args) {
print(5);
}
}
Complexity
The time complexity of given solution is O(n) and space complexity is O(1).