SWEA 1234 [S/W 문제해결 기본] 10일차 - 비밀번호

for test_case in range(1, 11):
    stack = []
    n, nums = input().split()
    nums = list(nums.strip())

    for num in nums:
        if not stack:
            stack.append(num)
        else:
            if stack[-1] == num:
                stack.pop()
            else:
                stack.append(num)

    print('#' + str(test_case), ''.join(stack))