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====== Codeforces Round #394 (Div. 2) ======
====== D ======
===== 题意 =====
给数列 a, 排列 c,长度均为 n,找出数列 b 使得数列 b-a 中元素的大小顺序同 c 一样。a, b 中所有元素均在 $[l, r]$ 内。
$1\le n\le 10^5$
===== 思路 =====
这个我觉得直接暴力 assign 再调整
a 1 1 1 1 1\\
b 4 2 6 5 3\\
c 3 1 5 4 2
a 3 4 8 9\\
b 6 6 9 13\\
c 3 2 1 4
====== E ======
===== 题意 =====
用平行于坐标轴的线段画出一棵树,一条树边对应一条线段,仅在树上结点对应的坐标相交,问是否可行,给出方案。
点数不超过 30
===== 思路 =====
我觉得这个就很好构造
你看 30,我不妨直接:与根相连的边长用 $2^{30}$,往下一层边长减少一倍,这样可以保证碰不着。
====== F ======
===== 题意 =====
给一张图片,字母矩阵形式
它有 $k$ 个副本,每个副本由原图将一块矩形区域刷成另一种颜色而成。定义两个副本之间的距离是所有对应像素对应的字母序数差的绝对值的和。求到所有其他副本的距离的和最小的那个副本。
===== 题解 =====
题解说拼命二维前缀和 ..