Your task is to implement the function strstr. The function takes two strings as arguments (s,x) and locates the occurrence of the string x in the string s. The function returns and integer denoting the first occurrence of the string x in s.
The first line of input contains an integer T denoting the no of test cases . Then T test cases follow. The first line of each test case contains two strings s and x.
For each test case, in a new line, output will be an integer denoting the first occurrence of the x in the string s. Return -1 if no match found.
Since this is a function problem, you don't have to take any input. Just complete the strstr function.
1 <= T <= 100
1<= |s|,|x| <= 1000
Testcase 1: Fr is not present in the string GeeksForGeeks as substring.
Testcase 2: For is present as substring in GeeksForGeeks from index 5.