AtCoder Grand Contest 056
C
01 Balanced
AtCoder
⌀ 2481
原题
← BD →
翻译中…

Problem Statement

翻译中…

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 $s$.

翻译中…

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.

翻译中…

Constraints

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

Input

翻译中…

Input is given from Standard Input in the following format:

翻译中…

N M
L_1 R_1
L_2 R_2
\vdots
L_M R_M

翻译中…

Output

翻译中…

Print the answer.

翻译中…

样例

Input #1
4 2
1 2
3 4
Output #1
0101
Input #2
6 2
1 4
3 6
Output #2
001100
Input #3
20 10
6 17
2 3
14 19
5 14
10 15
7 20
10 19
3 20
6 9
7 12
Output #3
00100100101101001011
题目信息
题号
agc056_c
时间限制
5 s
内存限制
1024 MB

题面与样例版权归 AtCoder 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。