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???????????????????????????????? '1'?'2' ? '3'?????????????? 0?

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import sys
def find_min_length(s):
    last_pos = {'1': -1, '2': -1, '3': -1}
    min_len = float('inf')
    left = 0
    for right in range(len(s)):
        c = s[right]
        last_pos[c] = right
        if (last_pos['1'] >= left and
            last_pos['2'] >= left and
            last_pos['3'] >= left):
            current_len = right - left + 1
            if current_len < min_len:
                min_len = current_len
            # Move left pointer
            left_char = s[left]
            last_pos[left_char] -= 1
            left += 1
    return min_len if min_len != float('inf') else 0
def main():
    t = int(sys.stdin.readline())
    for _ in range(t):
        s = sys.stdin.readline().strip()
        print("{0:.9f}".format(find_min_length(s)))
if __name__ == "__main__":
    main()

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?????????? O(n)?????????????