Last Index of Element

The task is to determine the index of the last occurrence of a specified element x within an array that may contain duplicate elements. If the element is not present, return -1.

Input:

The first line contains an integer N representing the size of the array. The next line contains N space-separated integers representing the elements of the array. The last line contains an integer 'x' whose index has to be found.

Output:

The only line of the output prints the Index or -1.

Example:

Input:

N = 5
arr = [2, 3, 4, 2, 5]
x = 2

Output:

3

Explanation:

The last occurrence of the element 2 is at the index 3 in the array.

Constraints:

1

Question

Last Index of Element

The task is to determine the index of the last occurrence of a specified element x within an array that may contain duplicate elements. If the element is not present, return -1.

Input:

The first line contains an integer N representing the size of the array.

The next line contains N space-separated integers representing the elements of the array.

The last line contains an integer 'x' whose index has to be found.

Output:

The only line of the output prints the Index or -1.

Example:

Input:

N = 5
arr = [2, 3, 4, 2, 5]
x = 2

Output:

Explanation:

The last occurrence of the element 2 is at the index 3 in the array.

Constraints:

1 <= N <= 10^3
1 <= arr[i] <= 10^9
1 <= x < N

Note:

Consider 0-based indexing for the array.

Accepted Answer

Find the index of the last occurrence of a specified element in an array.

Iterate through the array from right to left to find the last occurrence of the element.
Return the index if found, otherwise return -1.
Consider 0-based indexing for the array.

Accepted Answer

def last_index_of_element(arr, x):
    for i in range(len(arr) - 1, -1, -1):
        if arr[i] == x:
            return i
    return -1
N = int(input())
arr = list(map(int, input().split()))
x = int(input())
print(last_index_of_element(arr, x))

Asked in IEO Makers Fablab