import java.util.*;
 
 /**
 Lab 3, Assignment 2,
 test-like main class that asks for a size and prints the matrix
*/ 

 public class ass2{
     public static void main(String [] args){
         int degree;
         Scanner s = new Scanner(System.in);
         System.out.println("How large?");
         degree = s.nextInt();
         Matrix m = new Matrix(degree);
         m.createArray();
         m.printMatrix();
     }
 }
 
 /**
 Creates/outputs a pretty matrix for Lab3, Assignment 2
 */
 class Matrix{
     private int degree;
     
     /**
     Creates a new matrix for Lab 3, Assignment 2
     @param degree the degree of the matrix (N X N)
     */
     public Matrix(int degree){
     if(degree<=0){
         throw new IllegalArgumentException("Degree must be a positive integer");
     }
     else{
         this.degree=degree;
     }
     }
     
     /**
     Populates the matrix with the correct values
     @return int returns the matrix as a two-dimensional int
     */
     public int[][] createArray(){
         int [][] matrix = new int[degree][degree];
         //first init row 0 to 0
         for(int i=0;i<=degree;i++){
             matrix [0][i]=0;
         }
         //then set col 0 to 1
         for(int j=0;j<=degree;j++){
             matrix[j][0]=1;
         }
         //then do the rest of the calcs and fill in the matrix
         for(int j=1;j<=degree;j++){        //do row
             for(int i=1;i<=degree;i++){    //do element
                 matrix[i][j]=matrix[i-1][j-1]+matrix[i-1][j];
             }
         }
         return matrix[][];
     }
     
     /**
     Redfines the degree of the matrix
     @param int the new degree of the matrix (N X N)
     */
     public void setDegree(int degree){
     if(degree<=0){
         throw new IllegalArgumentException("Degree must be a positive integer");
     }
     else{
         this.degree=degree;
     }
     }
     
     /**
     Prints the matrix to the terminal
     */
     public void printMatrix(){
         for(int j=1;j<=degree;j++){        //do row
             for(int i=1;i<=degree;i++){    //do element
                 if(matrix[i][j]==0){
                     System.out.print("  ");
                 }
                 else{
                     System.out.print(matrix[i][j]+" ");
                 }
             }
         }
     }
 }