#描述#
We call [a,b] an interval where a < b. we call [a,b] is an nested interval of [c,d] where c < a and b < d.
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Here comes the problem. You are given N intervals, calculate the number of interval who is a nested interval of another.

#格式#
##输入格式##
Several test case.
Every case, first line an integer N(1&lt=N&lt=100000). Then N lines, two integer a,b for each line(0&lt=a&ltb&lt=10^9);
I guarantee that in every test case, there will be no integer appear twice or more.

##输出格式##
The result.

#样例1#
##样例输入1##

1
1 1000000000

2
5 6
2 9

5
1 10
2 9
3 8
4 7
5 6

##样例输出1##

0
1
4

#限制#
1000ms
32768KB

#提示#

#来源#
dd