```go
package main

import (
	"bufio"
	"fmt"
	"os"
)

func main() {
	in := bufio.NewReader(os.Stdin)
	var n, k int
	if _, err := fmt.Fscan(in, &n, &k); err != nil {
		return
	}

	a := make([]int, n)
	for i := 0; i < n; i++ {
		fmt.Fscan(in, &a[i])
	}

	best := 1
	cur := 1
	for i := 1; i < n; i++ {
		if a[i] != a[i-1] {
			cur++
		} else {
			cur = 1
		}
		if cur > best {
			best = cur
		}
	}

	if n == 0 {
		best = 0
	}
	fmt.Print(best)
}
```