P5850 [CF1389F] Bicolored Segments
省选
题目描述

You are given $n$ segments $[l_1, r_1], [l_2, r_2], \dots, [l_n, r_n]$. Each segment has one of two colors: the $i$-th segment's color is $t_i$.

Let's call a pair of segments $i$ and $j$ bad if the following two conditions are met:

  • $t_i \ne t_j$;
  • the segments $[l_i, r_i]$ and $[l_j, r_j]$ intersect, embed or touch, i. e. there exists an integer $x$ such that $x \in [l_i, r_i]$ and $x \in [l_j, r_j]$.

Calculate the maximum number of segments that can be selected from the given ones, so that there is no bad pair among the selected ones.

Input

The first line contains a single integer $n$ ($1 \le n \le 2 \cdot 10^5$) — number of segments.

The next $n$ lines contains three integers $l_i, r_i, t_i$ ($1 \le l_i \le r_i \le 10^9; t_i \in \{1, 2\}$) — description of the $i$-th segment.

Output

Print the maximum number of segments that can be selected, so that there is no bad pair among the selected segments.

输入格式

见题面 Input 部分

输出格式

见题面 Output 部分

样例输入
3 1 3 1 4 6 2 2 5 1
样例输出
2