Python: Find the indices for which the numbers in the list drops
Python Programming Puzzles: Exercise-23 with Solution
Write a Python program to find the indices for which the numbers in the list drops.
NOTE: You can detect multiple drops just by checking if nums[i] < nums[i-1].
Input: [0, -1, 3, 8, 5, 9, 8, 14, 2, 4, 3, -10, 10, 17, 41, 22, -4, -4, -15, 0] Output: [1, 4, 6, 8, 10, 11, 15, 16, 18] Input: [6, 5, 4, 3, 2, 1] Output: [1, 2, 3, 4, 5] Input: [1, 19, 5, 15, 5, 25, 5] Output: [2, 4, 6]
Sample Solution-1:
Python Code:
#License: https://bit.ly/3oLErEI
def test(nums):
drop_indices = []
for i in range(1, len(nums)):
if nums[i] < nums[i - 1]:
drop_indices.append(i)
return drop_indices
nums = [0, -1, 3, 8, 5, 9, 8, 14, 2, 4, 3, -10, 10, 17, 41, 22, -4, -4, -15, 0]
print("Original list:")
print(nums)
print("Indices for which the numbers of the said list drops.:")
print(test(nums))
nums = [6,5,4,3,2,1]
print("\nOriginal list:")
print(nums)
print("Indices for which the numbers of the said list drops.:")
print(test(nums))
nums = [1,19,5,15,5,25,5]
print("\nOriginal list:")
print(nums)
print("Indices for which the numbers of the said list drops.:")
print(test(nums))
Sample Output:
Original list: [0, -1, 3, 8, 5, 9, 8, 14, 2, 4, 3, -10, 10, 17, 41, 22, -4, -4, -15, 0] Indices for which the numbers of the said list drops.: [1, 4, 6, 8, 10, 11, 15, 16, 18] Original list: [6, 5, 4, 3, 2, 1] Indices for which the numbers of the said list drops.: [1, 2, 3, 4, 5] Original list: [1, 19, 5, 15, 5, 25, 5] Indices for which the numbers of the said list drops.: [2, 4, 6]
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):
return [i for i in range(1, len(nums)) if nums[i] < nums[i - 1]]
nums = [0, -1, 3, 8, 5, 9, 8, 14, 2, 4, 3, -10, 10, 17, 41, 22, -4, -4, -15, 0]
print("Original list:")
print(nums)
print("Indices for which the numbers of the said list drops.:")
print(test(nums))
nums = [6,5,4,3,2,1]
print("\nOriginal list:")
print(nums)
print("Indices for which the numbers of the said list drops.:")
print(test(nums))
nums = [1,19,5,15,5,25,5]
print("\nOriginal list:")
print(nums)
print("Indices for which the numbers of the said list drops.:")
print(test(nums))
Sample Output:
Original list: [0, -1, 3, 8, 5, 9, 8, 14, 2, 4, 3, -10, 10, 17, 41, 22, -4, -4, -15, 0] Indices for which the numbers of the said list drops.: [1, 4, 6, 8, 10, 11, 15, 16, 18] Original list: [6, 5, 4, 3, 2, 1] Indices for which the numbers of the said list drops.: [1, 2, 3, 4, 5] Original list: [1, 19, 5, 15, 5, 25, 5] Indices for which the numbers of the said list drops.: [2, 4, 6]
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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Previous: Compute the sum of the ASCII values of the upper-case characters in a given string.
Next: Create a list whose ith element is the maximum of the first i elements of the input list.
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Python: Tips of the Day
Clamps num within the inclusive range specified by the boundary values x and y:
Example:
def tips_clamp_num(num,x,y): return max(min(num, max(x, y)), min(x, y)) print(tips_clamp_num(2, 4, 6)) print(tips_clamp_num(1, -1, -6))
Output:
4 -1
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