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
n = int(input())

a = []
b = []
for i in range(n):
  ab = input().split()
  a.append(int(ab[0]))
  b.append(int(ab[1]))
import statistics
a = statistics.median(a)
b = statistics.median(b)
if n % 2 != 0:
  print(int(b-a+1))
else:
  print(int(2*(b-a)+1))
