https://codeforces.com/contest/1139/problem/F

對(duì)于每個(gè)人， income inc為x，pref為y；

對(duì)于每道菜，price p和 standard s， beauty b

It is guaranteed that for all integers i from 1 to n, the following condition holds: pi≤si.

于是根據(jù)題意有

?pi≤incj≤si.

?和

|bi?prefj|≤(incj?pi)?

即

p[i]<=x<=s[i],??

?和

p[i]+b[i]<=x+y

p[i]?b[i]<=x?y

把所有出現(xiàn)的點(diǎn)都離散化一下，排序去重，然后開(kāi)始掃x軸

對(duì)于p[i]+b[i]和p[i]-b[i]這兩個(gè)函數(shù)，分別用2個(gè)樹(shù)狀數(shù)組去維護(hù)合法菜碟的個(gè)數(shù)