题目描述

自西向东延伸的铁路上坐落着$N$个城市，现有$M$列火车，

给出它们的出发城市 $L_i$ 和目标城市 $R_i$，$1 <= i <= m，$

回答$Q$次询问，每次询问给出$p_i$和$q_i$，输出出发城市序号大于等于$p_i$且目标城市序号小于等于$q_i$的火车的数量。

输入格式

Input is given from Standard Input in the following format:

$N$ $M$ $Q$

$L_1$ $R_1$

$L_2$ $R_2$

$:$

$L_M$ $R_M$

$p_1$ $q_1$

$p_2$ $q_2$

$:$

$p_Q$ $q_Q$

输出格式

Print $Q$ lines.

The $i$ -th line should contain the number of the trains that runs strictly within the section from City $p_i$ to City $q_i$ .

样例数据

$input$

2 3 1

1 1

1 2

2 2

1 2

$output$

3

$input$

10 3 2

1 5

2 8

7 10

1 7

3 10

$output$

1

1

$input$

10 10 10

1 6

2 9

4 5

4 7

4 7

5 8

6 6

6 7

7 9

10 10

1 8

1 9

1 10

2 8

2 9

2 10

3 8

3 9

3 10

1 10

$output$

7

9

10

6

8

9

6

7

8

10

数据规模与约定

• $N$ is an integer between $1$ and $500$ (inclusive).

• $M$ is an integer between $1$ and $200\ 000$ (inclusive).

• $Q$ is an integer between $1$ and $100\ 000$ (inclusive).

• $1\ \leq\ L_i\ \leq\ R_i\ \leq\ N$ $(1\ \leq\ i\ \leq\ M)$

• $1\ \leq\ p_i\ \leq\ q_i\ \leq\ N$ $(1\ \leq\ i\ \leq\ Q)$

时间限制：$1 \text {s}$

空间限制：$256 \text {MB}$