import java.util.*;

class Scratch {
    private static int visitedSet = 0;
    private static int[] visitedArr = new int[16];
    private static int[][] mat;

    public static void main(String[] args) {
        mat = getMatrix();
        prepareVisitedArr(visitedArr);

        for (int i = 0; i < mat.length; i++) {
            for (int j = 0; j < mat[0].length; j++) {
                if (i == 0 || j == 0 || i == mat.length - 1 || j == mat.length - 1) {
                    if (mat[i][j] == 1) {
                        visitEntries(i, j);
                        visitedSet++;
                    }
                }
            }
        }

        for (int i = 0; i < mat.length; i++) {
            for (int j = 0; j < mat[0].length; j++) {
                if (mat[i][j] != -1) {
                    mat[i][j] = 0;
                }
            }
        }
    }

    private static void visitEntries(int i, int j) {
        if (visitedArr[i * mat.length + j] == -1) {
            visitedArr[i * mat.length + j] = visitedSet;

            if (i < mat.length - 1 && mat[i + 1][j] == 1) {
                visitEntries(i + 1, j);
            }

            if (j < mat.length - 1 && mat[i][j + 1] == 1) {
                visitEntries(i, j + 1);
            }

            if (i > 0 && mat[i - 1][j] == 1) {
                visitEntries(i - 1, j);
            }

            if (j > 0 && mat[i][j - 1] == 1) {
                visitEntries(i, j - 1);
            }
        }
    }

    private static void prepareVisitedArr(int[] visitedArr) {
        Arrays.fill(visitedArr, -1);
    }

    static int[][] getMatrix() {
        return new int[][] {
                {0,0,0,0},
                {1,0,1,0},
                {0,1,1,0},
                {0,0,0,0}
        };
    }
}