题解 | 吐泡泡

def rest(s):
    l = []
    for i in s:       
        while l :
            if l[-1] == 'o' and i == 'o':
                l.pop()
                i = 'O'           
            elif l[-1] == 'O' and i == 'O':
                l.pop()   
                i = None       
                break      
            else: 
                break
        if i is not None:
            l.append(i)
    return l
t = int(input())
for i in range(t):
    s = input().strip()
    result = rest(s)
    print(''.join(result))