Python program to find the largest among three numbers can be computed by comparing them with each other. A number x is said to be the largest among three numbers when its value is greater than other two numbers say y and z. For example, 20 is the largest among three numbers 10, 15, 20.

## 1. Algorithm to find the largest among three numbers

// $x$, $y$, $z$ are three input numbers//

1. Check if $x$ is greater or equal to $y$

2. If step [1] is true, then check if $x$ is greater or equal to $z$

3. If step [2] is true, then print $x$ is the largest

4. If step [2] is false, then print $z$ is the largest

5. If step [1] is false, then check if $y$ is greater or equal to $z$

6. If step [5] is true, then print $y$ is the largest

7. If step [5] is false then print $z$ is the largest

## 2. Pseudocode to find the largest among three numbers

Input: Three numbers $x$, $y$, $z$

Output: Largest among $x$, $y$, $z$

1. Procedure findLargest($x$, $y$, $z$):

2. If $x \geq y$:

3. If $x \geq z$:

4. Return $x$

5. Else:

6. Return $z$

7. Else:

8. If $y \geq z$:

9. Return $y$

10. Else:

11. Return $z$

12. End Procedure

## 3. Time Complexity to find the largest among three numbers

Time Complexity: O(1)

## 4. Python Program to find the largest among three numbers

Code has been copied
# **************************************************
#                alphabetacoder.com
# Python program to find largest among three numbers
# **************************************************

# take input of three numbers
numbers = input("Enter the numbers = ").split()

# fetch each numbers
x = int(numbers[0])
y = int(numbers[1])
z = int(numbers[2])

# find the largest number
if x >= y:
if x >= z:
print(x, " is the largest number.")
else:
print(z, " is the largest number.")
else:
if y >= z:
print(y, " is the largest number.")
else:
print(z, " is the largest number.")


Output

#### Case 1:

Enter the three numbers = -13 -18 -23

-13 is the largest number.

#### Case 2:

Enter the three numbers = 10 20 30

30 is the largest number.