Given an integer N, the task is to find N elements which fail the below-sorting algorithm. If none of the N elements fail, then print -1.
loop i from 1 to n-1 loop j from i to n-1 if a[j]>a[i+1] swap(a[i], a[j+1])
Input: N = 10 Output: 10 9 8 7 6 5 4 3 2 1 Input: N = 2 Output: -1
Approach: On solving for various cases, we can observe that only for n<=2, the given algorithm is invalid. Any value of N above that will fail on the given algorithm. A sorted array consisiting of N numbers(1, 2, 3 . . N) in reverse order cannot be sorted using this given algorithm.
Below is the implementation of the above approach:
3 2 1
Time Complexity: O(N)
Auxiliary Space: O(1)
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