public class ZigZagPrintMatrix {

public static void printZigZagMatrix(int[][] matrix) {

int tr = 0;

int tc = 0;

int dr = 0;

int dc = 0;

int endR = matrix.length - 1;

int endC = matrix[0].length - 1;

boolean fromUp = false;

while (tr != endR + 1) {

printLevel(matrix, fromUp, tr, tc, dr, dc);

tr = tc == endC ? tr + 1 : tr;

tc = tc == endC ? tc : tc + 1;

dc = dr == endR ? dc + 1 : dc;

dr = dr == endR ? dr : dr + 1;

fromUp = !fromUp;

}

System.out.println();

}

public static void printLevel(int[][] m, boolean direction, int tr, int tc, int dr, int dc) {

if (direction) {

while (tr != dr + 1) {

System.out.print(m[tr++][tc--] + " ");

}

} else {

while (dr != tr - 1) {

System.out.print(m[dr--][dc++] + " ");

}

}

}

public static void main(String[] args) {

int[][] matrix = {{1, 2, 3, 4}, {5, 6, 7, 8}, {9, 10, 11, 12}};

printZigZagMatrix(matrix);

}

}