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cherryteresa cherryteresa is offline Offline
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How to Sum a Pascal Triangle

 
0
  #1
Dec 3rd, 2008
Hi there. I had to make a code to print out a Pascal Triangle. But I'm not getting it to display properly.

For example, if the user types in 4, then it will print:
1
1
1 2
1 3 3

But it should print
1
1 1
1 2 1
1 3 3 1


And the last thing I'm trying to figure out is how to make it show a sum of the numbers.
So it should add:
.. 1
.. 1 + 1
.. 1 + 2 + 1
+ 1 + 3 + 3 + 1
.. 15 <-----------and display this as the sum.

Any help is appreciated. Thank you!

#include <stdlib.h>
#include <stdio.h>
#include <fstream>
#include <iostream>
#include <ctype.h>  // I know some of these may be unnecessary 
#include <string> // but our teacher wants us to include
#include <iomanip> // these in all our code.
#include <math.h> 
using namespace std;
int sum, i, size;
void inputSize();
void sumNumbers();
 
void main(int size) 
{
	int sum=0;
	cout<<"Pascal Triangle:\n";
	inputSize();
}

void inputSize()
{
	cout<< "Enter the amount of rows (between 1 and 9) you would like in the triangle."<<endl;
	cin >>size;
	cout<<"\n";	

	if (size > 0 && size <10)
	{	
		int *rowA = new int[1];
		rowA[0] = 1;
		cout <<setw(6)<<rowA[0] <<endl;
 
		for (int x = 1; x < size; x++) 
		{
			int *rowB = new int[x+1];
			rowB[0] = rowA[0];
			for (int y = 1; y < x; y++)
				rowB[y] = rowA[y-1] + rowA[y];
				rowB[x] = rowA[x-1];
														 
			delete [] rowA;
			rowA = rowB;
 
			for (int y = 0; y < x; y++)
			cout <<setw(6)<< rowB[y];
			cout <<"\n";
		}
		delete [] rowA;

		sumNumbers();
	}

	else
	{ cout<< "Number is not between 1-9.\n"<<endl; }
}
		
void sumNumbers()                           
{
	for (int x=0; x<size; x++)
	{
		for (int y=0; y<size; y++)
		{
			sum +=y;  // This is totally wrong, 
                }                         // I can't figure out how to 
		cout<<sum<<"\n"<<endl; //make a sum of the numbers
	}
}


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