Pascal’s Triangle Printing – Computer Sir Ki Class

Code Learning #CPP#3173

Pascal’s Triangle Printing

Printing a pascal’s triangle of given number of rows.

Learning Objectives

• Printing pascal’s triangle of numbers.

Source Code

 #include using namespace std; int main() { int r; cout<<"Enter number of r: "; cin>>r; int m=1; for(int i=0;i

Run Output

``````Enter number of rows: 5
1
1   1
1   2   1
1   3   3   1
1   4   6   4   1``````

Code Understanding

int r; cout<<“Enter number of r: “; cin>>r;
Collecting number of rows from the user.

int m=1; //The multiplier for calculation of pascal’s number value initialised with 1

for(int i=0;i<r;++i) //Outer loop for row counting
{

for(int sp = 1; sp <= r-i; sp++)  cout <<” “;  //Loop for space before the first number in a row
for(int j=0;j<=i;j++)  //Inner loop for column in each row
{
if (j==0||i==0)m=1;     //First row has just 1 to be printed.
else m = m*(i-j+1)/j;    //In other row we calculate pascal’s value by given expression.
cout<<m<< ” “;             //Printing the number followed by some space to make a proper formation
}
cout << endl;                    //Changing row after each iteration
}

Notes

• The code given above is optimised for 5 row. For other count some adjustments in initial spaces and inter character spaces may be required for proper visibility of the triangle.
• There are many special properties of numbers in the pascal’s triangle of numbers. Following link makes an interesting readout.
https://en.wikipedia.org/wiki/Pascal%27s_triangle

Suggested Filename(s): pascaltr.cpp

sunmitra| Created: 29-Jan-2018 | Updated: 29-Jan-2018|

×