spoj#TWIST. Twist and whirl - want to cheat

Twist and whirl - want to cheat

English Vietnamese

A well-known sharper I*** invented a new way to swindle people. There are N thimbles on the table, and there is a small ball with the number under each of them. The balls are numbered with numbers from 1 to N from left to right. At one operation I*** changes the order of some subsequence of successive thimbles to the opposite. Your task is to find the order of numbers (from left to right) in sequence after all of his manipulations. The total number of manipulations is M.

Input
The first line contains two integer numbers N and M (1<=N<=100000, 1<=M<=100000) separated by a space. Each of the following M lines contains two integer numbers Pi, Qi (1<=Pi<=Qi<=N) - positions of the leftmost and rightmost thimbles in rotated sequence.

Output
Output the sequence of N numbers - the numbers of balls in the thimbles from left to right.

Sample test(s)

Input
Test #1
5 2
1 3
4 5

Test #2
5 2
1 4
2 5

Output
Test #1
3 2 1 5 4

Test #2
4 5 1 2 3

Note: A naive solution would result in TLE. Have fun! :D