1071: 对称二叉树
Time Limit: 1 Sec
Memory Limit: 128 MB
Submission：2
AC：2
Score：100.00
Description
Input
Output
Samples
input:
10
2 2 5 5 5 5 4 4 2 3
9 10
-1 -1
-1 -1
-1 -1
-1 -1
-1 2
3 4
5 6
-1 -1
7 8
output:
3
Hint
