KSzsh

摘要： 题目链接 题目描述： The gardener Kazimir Kazimirovich has an array of $n$ integers $c_1,c_2,…,c_n$. He wants to check if there are two different subsequences $ 阅读全文

摘要： 题目链接 题目描述： Cirno_9baka has a paper tape with $n$ cells in a row on it. As he thinks that the blank paper tape is too dull, he wants to paint these cel 阅读全文