Finding a vector within another vector?

So I'm doing this assignment for a class, and need to write a function that will basically find all elements of a vector in another vector in the same exact order, then return the starting position of the sequence. Here's what I've tried:

It works fine as long as there are no repeated elements. For example, if I'm looking for a vector{1, 2, 3, 4} within vector {5, 6, 7, 1, 2, 3, 4, 2, 3}, it will come out fine, but if I try it with vector{1, 2, 3, 1, 2, 3, 4}, it fails on me.

re: Finding a vector within another vector?

It don't work at all - it return index as 'matching' element there matches first element of v2.
E.g if v2 = {1,1,2,3,4}; Hint - how many times does condition on line 7 execute?

re: Finding a vector within another vector?

Ah, actually I figured it out. Had to rewrite the two while loops and it worked fine.