103605: [Atcoder]ABC360 F - InterSections
Description
Score : $550$ points
Problem Statement
You are given $N$ intervals numbered $1$ to $N$. Interval $i$ is $[L_i, R_i]$.
Two intervals $[l_a, r_a]$ and $[l_b, r_b]$ are said to intersect if and only if they satisfy either $(l_a < l_b < r_a < r_b)$ or $(l_b < l_a < r_b < r_a)$.
Define $f(l, r)$ as the number of intervals $i$ ($1 \leq i \leq N$) that intersect with the interval $[l, r]$.
Among all pairs of integers $(l, r)$ satisfying $0 \leq l < r \leq 10^{9}$, find the pair $(l, r)$ that maximizes $f(l, r)$. If there are multiple such pairs, choose the one with the smallest $l$. If there are still multiple pairs, choose the one with the smallest $r$ among them. (Since $0 \leq l < r$, the pair $(l, r)$ to be answered is uniquely determined.)
Constraints
- $1 \leq N \leq 10^{5}$
- $0 \leq L_i < R_i \leq 10^{9}$ $(1 \leq i \leq N)$
- All input values are integers.
Input
The input is given from Standard Input in the following format:
$N$ $L_1$ $R_1$ $L_2$ $R_2$ $\vdots$ $L_N$ $R_N$
Output
Print the sought pair $(l, r)$ in the following format:
$l$ $r$
Sample Input 1
5 1 7 3 9 7 18 10 14 15 20
Sample Output 1
4 11
The maximum value of $f(l, r)$ is $4$, and among the pairs $(l, r)$ that achieve $f(l, r) = 4$, the smallest $l$ is $4$. The pairs $(l, r)$ that satisfy $f(l, r) = 4$ and $l = 4$ are the following three:
- $(l, r) = (4, 11)$
- $(l, r) = (4, 12)$
- $(l, r) = (4, 13)$
Among these, the smallest $r$ is $11$, so print $4$ and $11$.
Sample Input 2
11 856977192 996441446 298251737 935869360 396653206 658841528 710569907 929136831 325371222 425309117 379628374 697340458 835681913 939343451 140179224 887672320 375607390 611397526 93530028 581033295 249611310 775998537
Sample Output 2
396653207 887672321
Output
问题陈述
给你N个区间,编号从1到N。区间i是[L_i, R_i]。
如果两个区间[l_a, r_a]和[l_b, r_b]满足(l_a < l_b < r_a < r_b)或(l_b < l_a < r_b < r_a),则称这两个区间相交。
定义f(l, r)为与区间[l, r]相交的区间i(1 ≤ i ≤ N)的数量。
在所有满足0 ≤ l < r ≤ 10^9的整数对(l, r)中,找出使f(l, r)最大化的对(l, r)。如果有多个这样的对,选择l最小的对。如果还有多个对,从中选择r最小的一个。(由于0 ≤ l < r,要回答的对(l, r)是唯一确定的。)
约束条件
- 1 ≤ N ≤ 10^5
- 0 ≤ L_i < R_i ≤ 10^9 (1 ≤ i ≤ N)
- 所有输入值都是整数。
输入
输入从标准输入以以下格式给出:
$N$ $L_1$ $R_1$ $L_2$ $R_2$ $\vdots$ $L_N$ $R_N$
输出
以下列格式打印所求的对(l, r):
$l$ $r$
示例输入1
5 1 7 3 9 7 18 10 14 15 20
示例输出1
4 11
f(l, r)的最大值为4,在使f(l, r) = 4的(l, r)对中,最小的l为4。满足f(l, r) = 4和l = 4的对(l, r)有以下三个:
- (l, r) = (4, 11)
- (l, r) = (4, 12)
- (l, r) = (4, 13)
在这些中,最小的r为11,所以打印4和11。
示例输入2
11 856977192 996441446 298251737 935869360 396653206 658841528 710569907 929136831 325371222 425309117 379628374 697340458 835681913 939343451 140179224 887672320 375607390 611397526 93530028 581033295 249611310 775998537
示例输出2
396653207 887672321