Backtracking

Definition

一種用來做Brute Force的窮舉所有可能性的算法，本質是DFS，寫起來像決策樹的中序遍歷

Pattern

使用遞迴的話，基本pattern長這樣

result = []
def backtrack(path, options):
    if target_meet:
        result.append(path)
        return
    for option in options:
        # 做選擇
        backtrack(path, options)
        # 撤銷選擇