#P1061D. TV Shows

    ID: 4449 Type: RemoteJudge 2000ms 256MiB Tried: 0 Accepted: 0 Difficulty: (None) Uploaded By: Tags>data structuresgreedyimplementationsortings*2000

TV Shows

No submission language available for this problem.

Description

There are nn TV shows you want to watch. Suppose the whole time is split into equal parts called "minutes". The ii-th of the shows is going from lil_i-th to rir_i-th minute, both ends inclusive.

You need a TV to watch a TV show and you can't watch two TV shows which air at the same time on the same TV, so it is possible you will need multiple TVs in some minutes. For example, if segments [li,ri][l_i, r_i] and [lj,rj][l_j, r_j] intersect, then shows ii and jj can't be watched simultaneously on one TV.

Once you start watching a show on some TV it is not possible to "move" it to another TV (since it would be too distracting), or to watch another show on the same TV until this show ends.

There is a TV Rental shop near you. It rents a TV for xx rupees, and charges yy (y<xy < x) rupees for every extra minute you keep the TV. So in order to rent a TV for minutes [a;b][a; b] you will need to pay x+y(ba)x + y \cdot (b - a).

You can assume, that taking and returning of the TV doesn't take any time and doesn't distract from watching other TV shows. Find the minimum possible cost to view all shows. Since this value could be too large, print it modulo 109+710^9 + 7.

The first line contains integers nn, xx and yy (1n1051 \le n \le 10^5, 1y<x1091 \le y < x \le 10^9) — the number of TV shows, the cost to rent a TV for the first minute and the cost to rent a TV for every subsequent minute.

Each of the next nn lines contains two integers lil_i and rir_i (1liri1091 \le l_i \le r_i \le 10^9) denoting the start and the end minute of the ii-th TV show.

Print exactly one integer — the minimum cost to view all the shows taken modulo 109+710^9 + 7.

Input

The first line contains integers nn, xx and yy (1n1051 \le n \le 10^5, 1y<x1091 \le y < x \le 10^9) — the number of TV shows, the cost to rent a TV for the first minute and the cost to rent a TV for every subsequent minute.

Each of the next nn lines contains two integers lil_i and rir_i (1liri1091 \le l_i \le r_i \le 10^9) denoting the start and the end minute of the ii-th TV show.

Output

Print exactly one integer — the minimum cost to view all the shows taken modulo 109+710^9 + 7.

Samples

Sample Input 1

5 4 3
1 2
4 10
2 4
10 11
5 9

Sample Output 1

60

Sample Input 2

6 3 2
8 20
6 22
4 15
20 28
17 25
20 27

Sample Output 2

142

Sample Input 3

2 1000000000 2
1 2
2 3

Sample Output 3

999999997

Note

In the first example, the optimal strategy would be to rent 33 TVs to watch:

  • Show [1,2][1, 2] on the first TV,
  • Show [4,10][4, 10] on the second TV,
  • Shows [2,4],[5,9],[10,11][2, 4], [5, 9], [10, 11] on the third TV.

This way the cost for the first TV is 4+3(21)=74 + 3 \cdot (2 - 1) = 7, for the second is 4+3(104)=224 + 3 \cdot (10 - 4) = 22 and for the third is 4+3(112)=314 + 3 \cdot (11 - 2) = 31, which gives 6060 int total.

In the second example, it is optimal watch each show on a new TV.

In third example, it is optimal to watch both shows on a new TV. Note that the answer is to be printed modulo 109+710^9 + 7.