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Search an Element in an array

Problem​

Given an integer array and another integer element. The task is to find if the given element is present in array or not.

Examples:​

Example 1:

Input:
n = 4
arr[] = {1,2,3,4}
x = 3
Output: 2
Explanation: There is one test case with array as {1, 2, 3 4} and element to be searched as 3.  Since 3 is present at index 2, output is 2.

Example 2:

Input:
n = 5
arr[] = {1,2,3,4,5}
x = 5
Output: 4
Explanation: For array elements {1,2,3,4,5} element to be searched is 5 and it is at index 4. So, the output is 4.

Your Task:​

The task is to complete the function search() which takes the array arr[], its size N and the element X as inputs and returns the index of first occurrence of X in the given array. If the element X does not exist in the array, the function should return -1.

  • Expected Time Complexity: O(n)O(n)
  • Expected Auxiliary Space: O(1)O(1)

Constraints:​

  • 1<=n<=1061 <= n <= 10^6
  • 0<=arr[i]<=1060 <= arr[i] <= 10^6
  • 0<=x<=1050 <= x <= 10^5

Solution​

Python​

def search(self,arr, N, X):
    for i in range(0, N):
        if (arr[i] == X):
            return i
    return -1

Java​

static int search(int arr[], int N, int X) {
    for (int i = 0; i < N; i++) {
        if (arr[i] == X)
            return i;
    }
    return -1;
}

C++​

public:
int search(int arr[], int N, int X) {
    for (int i = 0; i < N; i++) {
        if (arr[i] == X)
            return i;
    }
    return -1;
}

C​

int search(int arr[], int N, int X) {
   for (int i = 0; i < N; i++) {
        if (arr[i] == X)
            return i;
    }
    return -1;
}
  • Time Complexity: O(n)O(n)
  • Auxiliary Space: O(1)O(1)