Python: Find the largest k numbers

Python Programming Puzzles: Exercise-36 with Solution

Write a Python program to find the largest k numbers from a given list of numbers.

Input: 
[1, 2, 3, 4, 5, 5, 3, 6, 2]
Output:
[6]
Input: 
[1, 2, 3, 4, 5, 5, 3, 6, 2]
Output:
[6, 5]
Input: 
[1, 2, 3, 4, 5, 5, 3, 6, 2]
Output:
[6, 5, 5]
Input: 
[1, 2, 3, 4, 5, 5, 3, 6, 2]
Output:
[6, 5, 5, 4]
Input: 
[1, 2, 3, 4, 5, 5, 3, 6, 2]
Output:
[6, 5, 5, 4, 3]

Pictorial Presentation:

Sample Solution-1:

Python Code:

 #License: https://bit.ly/3oLErEI

def test(nums, k):
    if k == 0:
        return []
    return sorted(nums, reverse=True)[:k]
nums = [1, 2, 3, 4, 5, 5, 3, 6, 2] 
print("Original list of numbers:",nums)
k = 1
print("Largest", k, "numbers from the said list:")
print(test(nums, k))
k = 2
print("Largest", k, "numbers from the said list:")
print(test(nums, k))
k = 3
print("Largest", k, "numbers from the said list:")
print(test(nums, k))
k = 4
print("Largest", k, "numbers from the said list:")
print(test(nums, k))
k = 5
print("Largest", k, "numbers from the said list:")
print(test(nums, k))

Sample Output:

Original list of numbers: [1, 2, 3, 4, 5, 5, 3, 6, 2]
Largest 1 numbers from the said list:
[6]
Largest 2 numbers from the said list:
[6, 5]
Largest 3 numbers from the said list:
[6, 5, 5]
Largest 4 numbers from the said list:
[6, 5, 5, 4]
Largest 5 numbers from the said list:
[6, 5, 5, 4, 3]

Flowchart:

Visualize Python code execution:

The following tool visualize what the computer is doing step-by-step as it executes the said program:

Sample Solution-2:

Python Code:

#License: https://bit.ly/3oLErEI

def test(nums, k):
    if k == 0:
        return []
    elif k == len(nums):
        return nums
    else:
        x = nums[0]
        for n in nums:
            if x < n:
                x = n
        result = [x]
        largest = nums[:]
        largest.remove(x)
        while len(result) != k:
            smallest = largest[0]
            for n in largest:
                if smallest < n:
                    smallest = n
            result.append(smallest)
            largest.remove(smallest)
        return result
nums = [1, 2, 3, 4, 5, 5, 3, 6, 2] 
print("Original list of numbers:",nums)
k = 1
print("Largest", k, "numbers from the said list:")
print(test(nums, k))
k = 2
print("Largest", k, "numbers from the said list:")
print(test(nums, k))
k = 3
print("Largest", k, "numbers from the said list:")
print(test(nums, k))
k = 4
print("Largest", k, "numbers from the said list:")
print(test(nums, k))
k = 5
print("Largest", k, "numbers from the said list:")
print(test(nums, k))

Sample Output:

Original list of numbers: [1, 2, 3, 4, 5, 5, 3, 6, 2]
Largest 1 numbers from the said list:
[6]
Largest 2 numbers from the said list:
[6, 5]
Largest 3 numbers from the said list:
[6, 5, 5]
Largest 4 numbers from the said list:
[6, 5, 5, 4]
Largest 5 numbers from the said list:
[6, 5, 5, 4, 3]

Flowchart:

Visualize Python code execution:

The following tool visualize what the computer is doing step-by-step as it executes the said program:

Python Code Editor :

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