Output Format

Output the minimum number of distinct item types.

6 5
1 3
3 2
2 3
3 1
2 5
5 4

4

Hint

The cows need at least $4$ different labels: first exchange $1$ for $3$, then $3$ for $2$, and finally $2$ for $5$.

$1\le N\le 5\times 10^4$, $1\le K\le 10^3$.

Translated by ChatGPT 5