C Program to find LCM of two numbers using Recursion
Input: N = 2, M = 4
Explanation: LCM of 2, 4 is 4.
Input: N = 3, M = 5
Explanation: LCM of 3, 5 is 15.
Approach: The idea is to use the basic elementary method of finding LCM of two numbers. Follow the steps below to solve the problem:
- Define a recursive function LCM() with 3 integer parameters N, M, and K to find LCM of N and M.
- The following base conditions need to be considered:
- If N or M is equal to 1, return N * M.
- If N is equal to M, return N.
- If K < min(N, M):
- If K divides both N and M, return K * LCM(N/K, M/K, 2).
- Otherwise, increment K by 1 and return LCM(N, M, K+1).
- Otherwise, return the product of N and M.
- Finally, print the result of the recursive function as the required LCM.
Below is the implementation of the above approach:
Time Complexity: O(max(N, M))
Auxiliary Space: O(1)