A river has $N$ checkpoints on left side and $M$ checkpoints on the right side. $P$ bridges are built connecting checkpoints across the river. Guards needs to be placed on checkpoints, a guard can protect all the bridges on which this checkpoint is present. There can be more than one guard to protect a single bridge.

Find the minimum number of guards required to protect all the bridges over the river.

Input Format:

• First line contains three space-separated integers $N \ M \ P$.
• Next $P$ lines contains two space separated integers $u \ v$ , denoting a bridge connecting the $u$ checkpoint on the left side to the $v$ checkpoint on the right side.

Output Format:

Print the minimum number of guards required to protect all the bridges over the river.

Constraints:

$1 \le N, M \le 2 \times 10^5 \\ 1 \le P \le 10^5 \\ 1 \le u \le N \\ 1 \le v \le M$