I am a teacher of Jiangsu college entrance examination. If I know anything, you can come to Baidu to ask questions. I can help you solve these puzzles at any time.
There is also this problem that allows you to express that k=0 and k do not exist in the process of solving.
Whether this question is 5 or 10, if you can express these two questions in the process of solving, you will get extra points.
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