How do you find the lcm of two numbers in python?

Question

In this program, you'll learn to find the LCM of two numbers and display it.

Nội dung chính Show

Program to Compute LCM
Program to Compute LCM Using GCD
How do you find the least common multiple of two numbers in Python?
How do you find the LCM in a for loop in Python?
How do you find LCM of two numbers?
What does LCM mean in Python?

To understand this example, you should have the knowledge of the following Python programming topics:

Python while Loop
Python Functions
Python Function Arguments
Python User-defined Functions

The least common multiple (L.C.M.) of two numbers is the smallest positive integer that is perfectly divisible by the two given numbers.

For example, the L.C.M. of 12 and 14 is 84.

Program to Compute LCM

# Python Program to find the L.C.M. of two input number

def compute_lcm(x, y):

   # choose the greater number
   if x > y:
       greater = x
   else:
       greater = y

   while(True):
       if((greater % x == 0) and (greater % y == 0)):
           lcm = greater
           break
       greater += 1

   return lcm

num1 = 54
num2 = 24

print("The L.C.M. is", compute_lcm(num1, num2))

Output

The L.C.M. is 216

Note: To test this program, change the values of num1 and num2.

This program stores two number in num1 and num2 respectively. These numbers are passed to the compute_lcm() function. The function returns the L.C.M of two numbers.

In the function, we first determine the greater of the two numbers since the L.C.M. can only be greater than or equal to the largest number. We then use an infinite while loop to go from that number and beyond.

In each iteration, we check if both the numbers perfectly divide our number. If so, we store the number as L.C.M. and break from the loop. Otherwise, the number is incremented by 1 and the loop continues.

The above program is slower to run. We can make it more efficient by using the fact that the product of two numbers is equal to the product of the least common multiple and greatest common divisor of those two numbers.

Number1 * Number2 = L.C.M. * G.C.D.

Here is a Python program to implement this.

Program to Compute LCM Using GCD

# Python program to find the L.C.M. of two input number

# This function computes GCD 
def compute_gcd(x, y):

   while(y):
       x, y = y, x % y
   return x

# This function computes LCM
def compute_lcm(x, y):
   lcm = (x*y)//compute_gcd(x,y)
   return lcm

num1 = 54
num2 = 24 

print("The L.C.M. is", compute_lcm(num1, num2))

The output of this program is the same as before. We have two functions compute_gcd() and compute_lcm(). We require G.C.D. of the numbers to calculate its L.C.M.

So, compute_lcm() calls the function compute_gcd() to accomplish this. G.C.D. of two numbers can be calculated efficiently using the Euclidean algorithm.

Click here to learn more about methods to calculate G.C.D in Python.

This is a Python Program to find the LCM of two numbers.

Problem Description

The program takes two numbers and prints the LCM of two numbers.

Problem Solution

1. Take in both the integers and store it in separate variables.
2. Find which of the integer among the two is smaller and store it in a separate variable.
3. Use a while loop whose condition is always True until break is used.
4. Use an if statement to check if both the numbers are divisible by the minimum number and increment otherwise.
5. Print the final LCM.
6. Exit.

Program/Source Code

Here is source code of the Python Program to find the LCM of two numbers. The program output is also shown below.

a=int(input("Enter the first number:"))
b=int(input("Enter the second number:"))
if(a>b):
    min1=a
else:
    min1=b
while(1):
    if(min1%a==0 and min1%b==0):
        print("LCM is:",min1)
        break
    min1=min1+1

Program Explanation

1. User must enter both the numbers and store it in separate variables.
2. An if statement is used to find out which of the numbers is smaller and store in a minimum variable.
3. Then a while loop is used whose condition is always true (or 1) unless break is used.
4. Then an if statement within the loop is used to check whether the value in the minimum variable is divisible by both the numbers.
5. If it is divisible, break statement breaks out of the loop.
6. If it is not divisible, the value in the minimum variable is incremented.
7. The final LCM is printed.

Runtime Test Cases

 
Case 1:
Enter the first number:5
Enter the second number:3
LCM is: 15
 
Case 2:
Enter the first number:15
Enter the second number:20
LCM is: 60

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Manish Bhojasia, a technology veteran with 20+ years @ Cisco & Wipro, is Founder and CTO at Sanfoundry. He lives in Bangalore, and focuses on development of Linux Kernel, SAN Technologies, Advanced C, Data Structures & Alogrithms. Stay connected with him at LinkedIn.

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How do you find the least common multiple of two numbers in Python?

How to find LCM of more than two numbers?.

from math import gcd..

list1 = [12,48,8,60].

lcm = list1[0].

for i in list1[1:]:.

lcm = int(lcm*i/gcd(lcm, i)).

print("least common multiple = ", lcm).

How do you find the LCM in a for loop in Python?

Step 1:Initially, Get 2 Integer Inputs from the user using int(input()). Step 2:Find the greater number by using an If condition and assign it to the variable 'max'. Step 3:Within the while loop, Use an If condition to check whether the remainder of (max% a) and (max% b) equals to zero or not.

How do you find LCM of two numbers?

Therefore, the formula to find LCM of two numbers is, LCM of two numbers = product of two numbers ÷ HCF of two numbers. Note: The LCM of two co-prime numbers is equal to the product of co-prime numbers because the highest common factor of prime numbers is 1.

What does LCM mean in Python?

The Least Common Multiple (LCM) is also referred to as the Lowest Common Multiple (LCM) and Least Common Divisor (LCD). For two integers a and b, denoted LCM(a,b), the LCM is the smallest positive integer that is evenly divisible by both a and b.

programming python