/**
 * 
 * 
 * @author sank
 */
public class IntQueue {
    static int[][] matrix;

    public int[][] getMatrix(int size) {
        matrix = new int[size][size];
        int row = 0;
        Position point = new Position(0, 0);
        for (int i = 1; i < size * size + 1; i++) {
            matrix[point.y][point.x] = i;
            point = findNextPostion(point,size);
        }
        return matrix;
    }

    Position findNextPostion(Position p,int size) {
        Position rtl = new Position(p.x,p.y);        
        if (rtl.y != 0 && rtl.x != size - 1) {
            rtl.y = rtl.y -1;
            rtl.x = rtl.x +1;
        } else {
            int backSize = rtl.x;
            for (int i = 0; i < backSize; i++) {
                rtl.y ++;
                rtl.x --;
                if (rtl.y == size - 1 || rtl.x == 0) {
                    break;
                }
            }
            if (rtl.y == size - 1) {
                rtl.x ++;
            }
            if (rtl.x == 0 && rtl.y != size - 1) {
                rtl.y ++;
            }            
        }        
        return rtl;
    }

    public static void main(String[] args) {
        int size = 4;
        IntQueue intQueue = new IntQueue();
        matrix = intQueue.getMatrix(size);
        for (int i = 0; i < size; i++) {
            for (int j = 0; j < size; j++) {
                System.out.print(matrix[i][j] + " ");
            }
            System.out.print("\n");
        }
    }
}

class Position {
    public int x;
    public int y;
    Position() {
       this(0,0);
    }
    Position(int x, int y) {
        this.x = x;
        this.y = y;
    }
}

/* this class print a square matrix diagonally, like this
 * 1 3 6 10 
 * 2 5 9 13 
 * 4 8 12 15 
 * 7 11 14 16 
 */
public class Diagonal {
  public static void main(String[] args) {
    int size = 4; // size can be from 1 - infinity
    int m[][] = new int[size][size];
    
    int last = 0;
    for(int i=0; i<2*size-1; i++){
      int max = i < size ? i+1 : size*2-1 - i;  // element count in this slice
      int r = i < size ? i : size-1;   // row
      int c = i - r;                   // column
      for(int j=0; j<max; j++){
        //System.out.println(r+","+c+":"+last + "  i=" +i+", j="+j+", m="+ max);
        m[r--][c++]= ++last;
      }
    }
    
    for(int i=0; i<size; i++){
      for(int j=0; j<size; j++)
        System.out.print(m[i][j] + " ");
      System.out.println();
    }
  }
}