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Check if a List is Sorted

Certification: Basic Level Accuracy: 42.37% Submissions: 59 Points: 5

Write a Python program that determines whether a given list of numbers is sorted in ascending order.

Example 1
    

  • Input: list = [1, 2, 3, 4, 5]
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  • Output: True
    • 

  • Explanation: 
      

    • Step 1: Compare each adjacent pair of elements starting from the first element.
      • 

    • Step 2: Check if element[i] <= element[i+1] for all indices i from 0 to n-2.
      • 

    • Step 3: Since all adjacent elements satisfy this condition, the list is sorted.
      • 

    • Step 4: Return True.
      • 

    •
Example 2
    

  • Input: list = [1, 3, 2, 4, 5]
    • 

  • Output: False
    • 

  • Explanation: 
      

    • Step 1: Compare each adjacent pair of elements starting from the first element.
      • 

    • Step 2: When checking elements at index 1 and 2, we find 3 > 2.
      • 

    • Step 3: Since this violates the ascending order condition, the list is not sorted.
      • 

    • Step 4: Return False.
      • 

    •
Constraints
    

  • 0 ≤ len(list) ≤ 10^6
    • 

  • List elements are integers
    • 

  • Time Complexity: O(n) where n is the length of the list
    • 

  • Space Complexity: O(1) as no additional space is needed
    •
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Hint
Solution

Solution Hints

    
  
  • Compare adjacent elements: all(nums[i] <= nums[i+1] for i in range(len(nums)-1))
    • 
  
  • Create a sorted copy and compare: sorted(nums) == nums
    • 
  
  • Use a loop to check each element against the next one
    •

Steps to solve by this approach:

 Step 1: Handle edge cases - empty lists or single-element lists are always considered sorted.

 Step 2: Iterate through the list up to the second-to-last element.

 Step 3: Compare each element with the next element in the list.

 Step 4: If any element is greater than the next element, the list is not sorted.

 Step 5: If we complete the iteration without finding any out-of-order elements, return True.

Submitted Code :