F. Rt Dg
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output

If you warm up before an action, you will have a high °C.

Input

You will be given $$$n - 1$$$ edges.

$$$$$$3 \le n \le 1000$$$$$$

Output

Print the answer.

Example
Input
3
1 2
2 3
Output
1