- Prepare
- Data Structures
- Advanced
- Mr. X and His Shots

# Mr. X and His Shots

# Mr. X and His Shots

A cricket match is going to be held. The field is represented by a 1D plane. A cricketer, Mr. X has favorite shots. Each shot has a particular range.
The range of the shot is from _{i} to _{i}. That means his favorite shot can be anywhere in this range. Each player on the opposite team
can field only in a particular range. Player can field from _{i} to _{i}. You are given the favorite shots of Mr. X and the range of players.

represents the strength of each player i.e. the number of shots player can stop.

Your task is to find:

.

**Game Rules**: A player can stop the shot if the range overlaps with the player's fielding range.

For more clarity about overlapping, study the following figure:

**Input Format**

The first line consists of two space separated integers, and .

Each of the next lines contains two space separated integers. The line contains and .

Each of the next lines contains two integers. The line contains integers and .

**Output Format**

You need to print the sum of the strengths of all the players: .

**Constraints**:

**Sample Input**

```
4 4
1 2
2 3
4 5
6 7
1 5
2 3
4 7
5 7
```

**Sample Output**

```
9
```

**Explanation**

*Player 1* can stop the 1st, 2nd and 3rd shot so the strength is .

*Player 2* can stop the 1st and 2nd shot so the strength is .

*Player 3* can stop the 3rd and 4th shot so the strength is .

*Player 4* can stop the 3rd and 4th shot so the strength is .

The sum of the strengths of all the players is .