Codeforces Round 906 (Div. 2)
E1
Doremy's Drying Plan (Easy Version)
Codeforces
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原题
← DE2 →
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The only differences between the two versions of this problem are the constraint on $k$, the time limit and the memory limit. You can make hacks only if all versions of the problem are solved.

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Doremy lives in a rainy country consisting of $n$ cities numbered from $1$ to $n$.

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The weather broadcast predicted the distribution of rain in the next $m$ days. In the $i$-th day, it will rain in the cities in the interval $[l_i, r_i]$. A city is called dry if it will never rain in that city in the next $m$ days.

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It turns out that Doremy has a special power. She can choose $k$ days (in the easy version, $k = 2$), and during these days it will not rain. Doremy wants to calculate the maximum number of dry cities after using the special power.

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Input

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The input consists of multiple test cases. The first line contains a single integer $t$ ($1\le t\le 10^4$) — the number of test cases. The description of the test cases follows.

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The first line contains three integers $n$, $m$ and $k$ ($1\le n\le 2\cdot 10^5$, $2 \le m \le 2\cdot 10^5$, $k = 2$) — the number of cities, the number of days, and the number of days of rain that Doremy can prevent.

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Then, $m$ lines follow. The $i$-th line contains two integers $l_i$, $r_i$ ($1\le l_i\le r_i\le n$) — the rain coverage on day $i$.

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It is guaranteed that the sum of $n$ and the sum of $m$ over all test cases do not exceed $2\cdot 10^5$.

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Output

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For each test case, output one integer — the maximum number of dry cities.

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Note

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In the first test case, if Doremy prevents

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  • rain $1,2$, then city $2$ will be dry;
  • rain $2,3$, then no city will be dry;
  • rain $1,3$, then no city will be dry;
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So there is at most $1$ dry city.

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In the second test case, if Doremy prevents

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  • rain $1,2$, then city $1,2$ will be dry;
  • rain $2,3$, then city $4,5$ will be dry;
  • rain $1,3$, then city $1,5$ will be dry.
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So there are at most $2$ dry cities.

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In the third test case, it is optimal to prevent rain $2,5$.

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In the forth test case, there is always $4$ days of rain that wets all the cities and cannot be prevented.

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样例

Input #1
6
2 3 2
1 2
1 2
1 1
5 3 2
1 3
2 4
3 5
10 6 2
1 5
6 10
2 2
3 7
5 8
1 4
100 6 2
1 100
1 100
1 100
1 100
1 100
1 100
1000 2 2
1 1
1 1
20 5 2
9 20
3 3
10 11
11 13
6 18
Output #1
1
2
3
0
1000
15
InputCopy OutputCopy
题目信息
题号
1890E1
时间限制
1 s
内存限制
256 MB

题面与样例版权归 Codeforces 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。