2019 ICPC 香港现场赛 复现

rank	solved	A	B	C	D	E	F	G	H	I	J	K
7	5	.	O	O	O	.	.	O	Ø	.	O	.

B

Solved by Henry.

C

Solved by XLor.

点分治，弄出所有 $(\sum,\max)$ 的点，推出式子后二维数点。

D

Solved by Henry.

G

Solved by Henry.

用 $2x$ 和 $2x+1$ 构造。

H

UnSolved by XLor.

写了个四维偏序，T 飞了。

见题解 2019 ICPC 香港现场赛 H. Hold the Line 题解。

J

Solved by Forsaken.

数位 dp。