题解 | 吐泡泡

t = int(input())
from collections import deque
for _ in range(t):
    s = input()
    stack = deque()
    for char in s:
        if not stack:
            stack.append(char)
        else:
            if stack[-1] == 'O':
                if char == 'O':
                    stack.pop()
                else:
                    stack.append(char)
            else:
                if char == 'o':
                    if len(stack)>=2 and stack[-2] == 'O':
                        stack.pop()
                        stack.pop()
                    else:
                        stack[-1] = 'O'
                else:
                    stack.append(char)
    print(''.join(stack))