Leftmost Index of X in given array

[Pushpit07]

Is your feature request related to a problem? Please describe.
In a sorted array of positive integers (elements may be repeated), the task is to find the leftmost index of a number x in the array.

Describe the solution you'd like
I would solve this problem using the principle of binary search

Do you want to work on it
C++

Please assign this to me under GSSoC

[motasimmakki]

/assign