How to write program to generate a pascal triangle in java?

[Aandaleeb]

Sponsored Links

Hi,
I am new to programming language. I recently started learning java language. Yesterday our sir has given us program like write a program to generate a pascal triangle in java?. I use various method but I unable to write that program. That's why I asked this question on this forum. So if you have any idea about this please help me.Thanks in advanced.

[Zecho]

Just tried to understand each and every steps.

class PascalTriangle 

{ 
public static void main(String args[]) 
{ 
int p=6; 
int triangle[][] = new int[p][p]; 
for(int q=0;q<p;q++) 
{ 
for(int r=0;r<p;r++) 
triangle[q][r]=0; 
} 
for(int q=0;q<p;q++) 
{ 
triangle[q][0]=1 ;
} 


for(int q=1;q<p;q++)
 { 
for(int r=1;r<p;r++) 
triangle[q][r]=triangle[q-1][r-1]+triangle[q-1][r]; } 

for(int q=0;q<p;q++) 
{ 
for(int r=0;r<=q;r++) 
System.out.print(triangle[q][r]+ " "); 
System.out.println(); 
} 



} 
}

[absolute55]

import java.io.*; 
public class TriPascal { 

public TriPascal() { 
} 

public static void main(String[] args) 
{ 
int step = new Integer(args[0]).intValue(); 
int col1 = nFilas * 2 - 1 ; 
int arrP[][] = new int[step][col1]; 
int cont = 0; 

for(int p=0;p<step;p++){ 
for(int q=0;q<col1;q++){ 
arrPascal[p][j]=0; 
} 
} 

arrP[0][step-1]=1; 
for(int p=1;p<step;p++){ 
for(int q=(step-1)-p;q<col1;q=j+2){ 
if(cont<=p){ 
if(q==0||q==col1-1){ 
arrP[p][q] = 1; 
}else{ 
arrP[p][q] = arrP[p-1][q-1] + arrP[p-1][q+1]; 
} 
} 
cont++; 
} 
cont = 0; 
} 
System.out.println("filas=" + step + "-Columnas=" + col1); 
for(int p=0;i<step;p++){ 
for(int q=0;q<col1;q++){ 
System.out.print(arrP[p][q]); 
} 
System.out.println(""); 
} 
} 

}

[Praetor]

Here I suggest you logic of your program just tried to understand.



step1.Make a new array with T number of elements and then insert left most element with value "1" and insert other with value "0"

step2.Now print all array.

step3. Now make use of for loop through the array like from N-1 ... I ... 0

a. Add the I element to the p+1 element. Store the result in the p element

b. If (p < T-2) goto a. Else, exit the loop

step4. Goto step 2

[opaper]

import java.io.;
import java.util.;
import gpdraw.;
import java.lang.;
public class pascal{
int[] array1= new int[10];
public void generate(int input)
{
int p=0;
for(int x=0;x<=input;x++){
for(int a=0 ;a<=n;a++){
arra1y[p] = fact(x)/(fact(x-a)fact(a));
p++;
}}
int b=0;
for (int row = 0; row <=input; row++){
for(int pos=0; pos<=row; pos++){
System.out.print(" " array1[d]);
b+;
}
System.out.println();

}}
public static int fact(int t){
if( t <= 1 ) 
return 1;
else
return t fact( t - 1 );
}
}

[Modifier]

public class Pascal {
    public static int[][] Rows(int p){
    	int[][] ptm = new int[p][];
    	for (int z = 0; z < p; z++) {
            ptm[z] = new int[z + 1];                          
            ptm[z][0] = 1;                          
            for (int q = 1; q< z; q++) {
              ptm[z][q] = ptm[z - 1][q - 1] + ptm[z - 1][q];  
            }
            ptm[z][z] = 1;                           
          }
          return ptm;
    }

 
    public static void main(String[] args) {
        if (args.length != 1) {
          System.out.println("usage: java " + Pascal.class.getName() + " rows");
          System.exit(1);
        }
        int p = Integer.parseInt(args[0]);
        if (p > 0) {
          int[][] pascal1 = Rows(n);
          for (int[] row1 : pascal1) {
    	for (int w : row1) System.out.print(w + " ");
    	System.out.println("");
          }
        }
      }
}

[Lekha Tikone]

hey also show output...

[EINSTEIN_007]

Originally Posted by Lekha Tikone

hey also show output...

I think that the simplest way to do it is probably to generate it line by line. Each line is based on the previous one.

1. Start with the first line (1)
2. Add a 1 first in the new line.
3. Add the first and second number in the previous line and put it on the new line, then the second and third, third and fourth and so on (this will be done zero times on the second row).
4. Finish by adding a last 1.
5. Begin a new line if you want one and jump to 2.