Find Final Ball Holder

You are given an array `receiver` of length `n`, where friends are numbered from `1` to `n`. If friend `i` currently holds the ball, then after one second they pass it to friend `receiver[i - 1]`. Initially, at time `0`, friend `1` has the ball. Given a non-negative integer `k`, return the friend number that holds the ball after exactly `k` seconds. Assume `k` can be very large, so a solution that simulates every second may be too slow. Example: - `receiver = [2, 4, 5, 3, 1]` - `k = 6` Ball movement: `1 -> 2 -> 4 -> 5 -> 3 -> 1 -> 2` Return `2`.