题目传送门:https://codeforces.com/problemset/problem/1189/B
题目大意:
给定一串长度为\(n\)的序列\(A(1\leqslant A_i\leqslant 10^9)\),问能否将序列\(A\)任意排序后,使得\(\forall i\in[1,n]\),都有\(A_i
由于序列\(A\)是环形构造,故我们认为\(A_0=A_{n},A_{n+1}=A_{1}\)
给序列\(A\)排序(降序),在任意一个位置放置\(A_1\)后,我们在其左边依次放置\(A_3,A_5,...A_{2k+1}\),在其右边依次放置\(A_{2},A_{4},...,A_{2k}\),由于序列是降序排列,故\(A_{2k},\(\alpha\)为任意非零整数
故我们仅需判断\(A_1是否成立即可
/*program from Wolfycz*/
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