Max Coins Collected by Tokens Moving Exactly 3 Steps Right on a 1D Board

You are given a 1D board represented by a string s of length n, containing multiple tokens and coins. Each token can move only to the right. Each move must be exactly 3 steps to the right (from index i to i+3), with no stopping in between. If a token lands on a cell containing a coin, it collects the coin (the coin is removed). A token may perform any number of moves as long as it stays within the board (i.e., i+3 < n). Compute the maximum number of coins that can be collected with an optimal strategy. Input (suggested): one line string s. Output: an integer, the maximum number of coins collectable. Constraints (suggested): 1 <= n <= 2e5. Example: Input: T..C..C.TC Output: 2 The example is illustrative; the exact character set (e.g., T token, C coin, . empty) should follow the original prompt. Example Input T..C..C.TC Output 2