Pascals Triangle In Java

Each row of a Pascals Triangle can be calculated from the previous row so the core of the solution is a method that calculates a row based on the previous row which is passed as input. Once we have that it is simply a matter of calling that method in a loop and formatting each row of the triangle.

The above animation of pascal triangle shows how Pascal's Triangle generates. 

Source Code in Java ( 5 rows ) :

public class Pascal{
    
    public static void main(String args[]) {
        
        int n = 5;           // Number of rows
        
        int[] row = new int[0];
        
        for(int i=0 ; i < n ; i++){
            
            row = nextRow(row);
            
            for(int j=0;j < n-i;j++){
                
                //Padding For Triangle
                System.out.print(" ");
                
            }
            //Output the values
            for(int j=0 ; j < row.length ; j++){
                
                System.out.print(row[j]+" ");
        
            }
            //Start New Line
            System.out.println();
        }
    }
    /*Find Values Of Next Row*/
    public static int[] nextRow(int row[]){
        
        int nextRow[] = new int [row.length+1];
        
        nextRow[0] = 1;               //First element always be 1
        nextRow[nextRow.length-1] =1; //Last element should be 1
        
        //generating rest values from the previous row
        for(int i=1 ; i < nextRow.length-1 ; i++){
            
            nextRow[i] = row[i-1] + row[i];
        }
        return nextRow;
    }
    
}