package main

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

func configure(scanner *bufio.Scanner) {
	scanner.Split(bufio.ScanWords)
	scanner.Buffer(make([]byte, 1000005), 1000005)
}
func getNextString(scanner *bufio.Scanner) string {
	scanned := scanner.Scan()
	if !scanned {
		panic("scan failed")
	}
	return scanner.Text()
}
func getNextInt(scanner *bufio.Scanner) int {
	i, _ := strconv.Atoi(getNextString(scanner))
	return i
}
func getNextInt64(scanner *bufio.Scanner) int64 {
	i, _ := strconv.ParseInt(getNextString(scanner), 10, 64)
	return i
}
func getNextFloat64(scanner *bufio.Scanner) float64 {
	i, _ := strconv.ParseFloat(getNextString(scanner), 64)
	return i
}
func main() {
	fp := os.Stdin
	wfp := os.Stdout
	extra := 0
	if os.Getenv("I") == "IronMan" {
		fp, _ = os.Open(os.Getenv("END_GAME"))
		extra = 100
	}
	scanner := bufio.NewScanner(fp)
	configure(scanner)
	writer := bufio.NewWriter(wfp)
	defer func() {
		r := recover()
		if r != nil {
			fmt.Fprintln(writer, r)
		}
		writer.Flush()
	}()
	solve(scanner, writer)
	for i := 0; i < extra; i++ {
		fmt.Fprintln(writer, "-----------------------------------")
		solve(scanner, writer)
	}
}
func solve(scanner *bufio.Scanner, writer *bufio.Writer) {
	h := getNextInt(scanner)
	w := getNextInt(scanner)
	aa := make([]bool, h*w)
	uf := make([]int, h*w)
	for i := 0; i < h*w; i++ {
		aa[i] = getNextInt(scanner) == 1
		uf[i] = i
	}
	for i := 0; i < h*w; i++ {
		if i-1 >= 0 && i%w != 0 && aa[i] && aa[i-1] {
			uf[root(i, uf)] = root(i-1, uf)
		}
		if i-w >= 0 && aa[i] && aa[i-w] {
			uf[root(i, uf)] = root(i-w, uf)
		}
	}
	m := map[int]int{}
	for i := 0; i < h*w; i++ {
		if !aa[i] {
			continue
		}
		m[root(i, uf)]++
	}
	fmt.Fprintln(writer, len(m))
}
func root(i int, uf []int) int {
	if i == uf[i] {
		return i
	}
	uf[i] = root(uf[i], uf)
	return uf[i]
}