#D3114. Bicolored Segments
Bicolored Segments
Bicolored Segments
You are given n segments [l_1, r_1], [l_2, r_2], ..., [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 ≠ 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 ∈ [l_i, r_i] and x ∈ [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 ≤ n ≤ 2 ⋅ 10^5) — number of segments.
The next n lines contains three integers l_i, r_i, t_i (1 ≤ l_i ≤ r_i ≤ 10^9; t_i ∈ {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.
Examples
Input
3 1 3 1 4 6 2 2 5 1
Output
2
Input
5 5 8 1 1 3 2 3 4 2 6 6 1 2 10 2
Output
4
Input
7 19 20 1 13 15 2 6 11 2 4 10 1 14 17 1 13 13 2 5 9 1
Output
5
inputFormat
Input
The first line contains a single integer n (1 ≤ n ≤ 2 ⋅ 10^5) — number of segments.
The next n lines contains three integers l_i, r_i, t_i (1 ≤ l_i ≤ r_i ≤ 10^9; t_i ∈ {1, 2}) — description of the i-th segment.
outputFormat
Output
Print the maximum number of segments that can be selected, so that there is no bad pair among the selected segments.
Examples
Input
3 1 3 1 4 6 2 2 5 1
Output
2
Input
5 5 8 1 1 3 2 3 4 2 6 6 1 2 10 2
Output
4
Input
7 19 20 1 13 15 2 6 11 2 4 10 1 14 17 1 13 13 2 5 9 1
Output
5
样例
7
19 20 1
13 15 2
6 11 2
4 10 1
14 17 1
13 13 2
5 9 1
5
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