题解 | 吐泡泡

def process_bubbles(s):
    stack = []
    for c in s:
        stack.append(c)
        while len(stack) >= 2:
            if stack[-2] == stack [-1] == "o":
                stack.pop()
                stack.pop()
                stack.append("O")
            elif stack[-2] == stack[-1] == "O":
                stack.pop()
                stack.pop()
            else:
                break
        
    return "".join(stack)

n = int(input())
for _ in range(n):
    string = input().strip()
    result = process_bubbles(string)
    print(result)