#D8761. Multiple of Nine

    ID: 7279 Type: Default 4000ms 1073MiB

Multiple of Nine

Multiple of Nine

Count the number of strings S that satisfy the following constraints, modulo 10^9 + 7.

  • The length of S is exactly N.
  • S consists of digits (0...9).
  • You are given Q intervals. For each i (1 \leq i \leq Q), the integer represented by S[l_i \ldots r_i] (the substring of S between the l_i-th (1-based) character and the r_i-th character, inclusive) must be a multiple of 9.

Here, the string S and its substrings may have leading zeroes. For example, 002019 represents the integer 2019.

Constraints

  • 1 \leq N \leq 10^9
  • 1 \leq Q \leq 15
  • 1 \leq l_i \leq r_i \leq N

Input

Input is given from Standard Input in the following format:

N Q l_1 r_1 : l_Q r_Q

Output

Print the number of strings that satisfy the conditions, modulo 10^9 + 7.

Examples

Input

4 2 1 2 2 4

Output

136

Input

6 3 2 5 3 5 1 3

Output

2720

Input

20 10 2 15 5 6 1 12 7 9 2 17 5 15 2 4 16 17 2 12 8 17

Output

862268030

inputFormat

Input

Input is given from Standard Input in the following format:

N Q l_1 r_1 : l_Q r_Q

outputFormat

Output

Print the number of strings that satisfy the conditions, modulo 10^9 + 7.

Examples

Input

4 2 1 2 2 4

Output

136

Input

6 3 2 5 3 5 1 3

Output

2720

Input

20 10 2 15 5 6 1 12 7 9 2 17 5 15 2 4 16 17 2 12 8 17

Output

862268030

样例

6
3
2 5
3 5
1 3
2720