题解 | 吐泡泡

import sys


def main():
    lines = sys.stdin.read().splitlines()
    T = len(lines)
    ret = []
    idx = -1
    for _ in range(T):
        idx += 1
        s = lines[idx]
        n = len(s)
        st = []
        for i in range(n):
            if len(st) == 0:
                st.append(s[i])
                continue
            if s[i] == "o":
                if st[-1] == "o":
                    st[-1] = "O"
                    if len(st) != 1 and st[-2] == "O":
                        st.pop()
                        st.pop()
                else:
                    st.append("o")
            else:
                if st[-1] == "O":
                    st.pop()
                else:
                    st.append("O")
        ret.append(''.join(st))
    sys.stdout.write("\n".join(ret))


if __name__ == "__main__":
    main()

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