Problem Statement

Consider making a string s of length N consisting of 0 and 1, where s must satisfy M conditions.
The i-th condition is represented by integers L_i and $R_i (1 \leq L_i < R_i \leq N)$.
This means that there should be equal numbers of 0 and 1 between the L_i-th and R_i-th characters (inclusive) of s.
Find the lexicographically smallest string s that satisfies all conditions.
It can be proved that the Constraints of the problem guarantee the existence of s that satisfies the conditions.

Input

Input is given from Standard Input in the following format:
N M
L_1 R_1
L_2 R_2
$\vdots$
L_M R_M

Output

Print the answer.

Constraints

• $2 \leq N \leq 10^6$
• $1 \leq M \leq 200000$
• $1 \leq L_i < R_i \leq N$
• $(R_i-L_i+1) \equiv 0 \mod 2$
• $(L_i,R_i) \neq (L_j,R_j) (i \neq j)$
• All values in input are integers.

Sample Input 1

4 2
1 2
3 4

Sample Output 1

0101

Sample Input 2

6 2
1 4
3 6

Sample Output 2

001100

Sample Input 3

20 10
6 17
2 3
14 19
5 14
10 15
7 20
10 19
3 20
6 9
7 12

Sample Output 3

00100100101101001011

见题面 Input 部分

见题面 Output 部分