p02661 AtCoder Beginner Contest 169 - Count Median
There are N integers X_1, X_2, \cdots, X_N, and we know that A_i \leq X_i \leq B_i. Find the number of different values that the median of X_1, X_2, \cdots, X_N can take.

Constraints

* 2 \leq N \leq 2 \times 10^5
* 1 \leq A_i \leq B_i \leq 10^9
* All values in input are integers.

Input

Input is given from Standard Input in the following format:


N
A_1 B_1
A_2 B_2
:
A_N B_N


Output

Print the answer.

Examples

Input

2
1 2
2 3


Output

3


Input

3
100 100
10 10000
1 1000000000


Output

9991
```python
N = int(input())

A = [0]*N
B = [0]*N

for i in range(N):
  A[i],B[i] = map(int, input().split())
A.sort()
B.sort()
 
if len(A)%2 != 0:
  ans = B[N//2]-A[N//2]+1
else:
  ans = (B[N//2]+B[N//2-1]) - (A[N//2]+A[N//2-1]) + 1

print(ans)
```