题目描述
There are 'n' coins kept on the table, numbered from 0 to 'n-1'. Initially, each coin is kept tails up. You have to perform two types of operations :
1) Flip all coins numbered between A and B inclusive. This is represented by the command:
0
A
B
2) Answer how many coins numbered between A and B inclusive are heads up. This is represented by the command
1
A
B
Input:
The first two lines contain two integers, N and Q.The first line after inputting N and Q has to be of form (1).Each of the next Q lines are of the form (2) as mentioned above.
Output:
Output 1 line for each of the queries of the form 2 containing the required answer for the corresponding query just after the query.
7
3
0
3
5
1
0
6
3 <-- this is the first output
1
3
4
2 <-- this is output
SAMPLE INPUT
7
3
0
3
5
1
0
6
1
3
4
SAMPLE OUTPUT
3
2
输入格式
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输出格式
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