LITE  Light Switching
Farmer John tries to keep the cows sharp by letting them play with intellectual toys. One of the larger toys is the lights in the barn. Each of the N (2 <= N <= 100,000) cow stalls conveniently numbered 1..N has a colorful light above it.
At the beginning of the evening, all the lights are off. The cows control the lights with a set of N pushbutton switches that toggle the lights; pushing switch i changes the state of light i from off to on or from on to off.
The cows read and execute a list of M (1 <= M <= 100,000) operations expressed as one of two integers (0 <= operation <= 1).
The first kind of operation (denoted by a 0 command) includes two subsequent integers S_i and E_i (1 <= S_i <= E_i <= N) that indicate a starting switch and ending switch. They execute the operation by pushing each pushbutton from S_i through E_i inclusive exactly once.
The second kind of operation (denoted by a 1 command) asks the cows to count how many lights are on in the range given by two integers S_i and E_i (1 <= S_i <= E_i <= N) which specify the inclusive range in which the cows should count the number of lights that are on.
Help FJ ensure the cows are getting the correct answer by processing the list and producing the proper counts.
Input
Line 1: Two spaceseparated integers: N and M
Lines 2..M+1: Each line represents an operation with three spaceseparated integers: operation, S_i, and E_i
Output
Lines 1..number of queries: For each output query, print the count as an integer by itself on a single line.
Example
Input:
4 5
0 1 2
0 2 4
1 2 3
0 2 4
1 1 4
Output:
1
2
hide comments
hippie:
20141217 14:16:53
There's nothing mysterious about the 10th testcase at all, a trivial flaw related to calculation of lit lights by combining lazy updates and current values was my cause of WA. Just go through the code carefully once. 

Igor Morozov:
20141102 12:30:24
Please, give some example with the same trick, as in test 10. I'm using segment tree with lazy propagation, updating the nodes everywhere, where needed, and pushing down correctly, still got WA. My code: http://ideone.com/Hh0mqL 

Chetan gulati:
20141025 20:30:22
Use faster input output to avoid TLE. 

Rishab Banerjee:
20141025 10:18:38
exactly same as flipcoin only difference is that flipcoin has 0 based indexing and here its 1 based costed me 5 WA 

Umair Khan:
20141022 07:39:59
Anyone going wrong at 10th test case, update the lazy node everywhere in the update method (I hope you get it).


caesar:
20141007 23:29:00
getting wrong answer on Test case 10. Any suggestion


maniAC:
20140708 21:18:54
Finally got AC after few TLE, just optimize the program using inline, TL should be 2.0 second :(. 

Archit Jain:
20140701 10:40:28
nice question


Atul Vaibhav:
20140416 16:25:08
i just copypasted my FLIPCOIN solution and got WA! but then read the problem details again "carefully" and got AC!


csprajeeth:
20140405 20:25:11
Same here..AC on FLIPCOINS and WA here

Added by:  Iqram Mahmud 
Date:  20100903 
Time limit:  1s 
Source limit:  50000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All except: OBJC VB.NET 
Resource:  USACO November 08 