Implement indexOf Function

You are provided with two strings A and B. Your task is to find the index of the first occurrence of A within B. If A is not found in B, return -1.

Example:

Input:

A = "bc", B = "abcddbc"

Output:

1

Explanation:

The substring "bc" is located at indices 1 and 5 (0-based index) in B, with the first occurrence at index 1.

Constraints:

• 1 <= T <= 100
• 1 <= |A|, |B| <= 5 * 10^4

Input:

The first line contains an integer 'T' which denotes the number of test cases or queries to be run. Then, the T test cases follow. The first and only line of each test case contains two strings A and B, separated by a single space.

Output:

For each test case, print the index of the first occurrence of A in B. If string A is not present in string B then print -1.

Note:

You do not need to print anything. It has already been taken care of. Just implement the given function.