import java.io.IOException; import java.io.InputStream; import java.math.BigInteger; import java.util.Arrays; import java.util.NoSuchElementException; import java.util.Scanner; public class Main implements Runnable { public static void main(String[] args) { new Thread(null,new Main(),"",Runtime.getRuntime().maxMemory()).run(); } public void run() { FastScanner sc = new FastScanner(); int H = sc.nextInt(); int W = sc.nextInt(); int[][] A = new int[H][W]; for (int i = 0; i < H; ++i) { for (int j = 0; j < W; ++j) { A[i][j] = sc.nextInt(); } } int col = -1; for (int i = 0; i < H; ++i) { for (int j = 0; j < W; ++j) { if (A[i][j] != 1) continue; go(W, H, j, i, A, col); --col; } } System.out.println(-col - 1); } void go(int W, int H, int x, int y, int[][] A, int col) { if (A[y][x] != 1) return; A[y][x] = col; for (int dx = -1; dx <= 1; ++dx) { for (int dy = -1; dy <= 1; ++dy) { if (Math.abs(dx) + Math.abs(dy) != 1) continue; if (x + dx >= W || x + dx < 0 || y + dy >= H || y + dy < 0) continue; if (A[dy + y][dx + x] == 1) { go(W, H, dx + x, dy + y, A, col); } } } } class FastScanner { private final InputStream in = System.in; private final byte[] buffer = new byte[1024]; private int ptr = 0; private int buflen = 0; private boolean hasNextByte() { if (ptr < buflen) { return true; } else { ptr = 0; try { buflen = in.read(buffer); } catch (IOException e) { e.printStackTrace(); } if (buflen <= 0) { return false; } } return true; } private int readByte() { if (hasNextByte()) return buffer[ptr++]; else return -1; } private boolean isPrintableChar(int c) { return 33 <= c && c <= 126; } public boolean hasNext() { while (hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++; return hasNextByte(); } public String next() { if (!hasNext()) throw new NoSuchElementException(); StringBuilder sb = new StringBuilder(); int b = readByte(); while (isPrintableChar(b)) { sb.appendCodePoint(b); b = readByte(); } return sb.toString(); } public long nextLong() { if (!hasNext()) throw new NoSuchElementException(); long n = 0; boolean minus = false; int b = readByte(); if (b == '-') { minus = true; b = readByte(); } if (b < '0' || '9' < b) { throw new NumberFormatException(); } while (true) { if ('0' <= b && b <= '9') { n *= 10; n += b - '0'; } else if (b == -1 || !isPrintableChar(b)) { return minus ? -n : n; } else { throw new NumberFormatException(); } b = readByte(); } } public int nextInt() { long nl = nextLong(); if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE) throw new NumberFormatException(); return (int) nl; } public double nextDouble() { return Double.parseDouble(next()); } } void tr(Object... objects) { System.out.println(Arrays.deepToString(objects)); } }