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This problem is in Contest(s) below:
Contest 1913:22计1-数组的应用-DS
Contest 1914:22计2-数组的应用-DS
Contest 1919:22数据1-数组的应用-DS-Copy
Contest 1923:22数据2-数组的应用-DS
Contest 2196:23计2-数组的应用-DS
Contest 2197:23计1-数组的应用-DS