- Write a C program to print pascal triangle till N rows by calculating binomial coefficients.
- Algorithm to print pascal triangle.

#### Required Knowledge

**Pascal Triangle** is a regular triangle of binomial coefficients. The counting of rows of the pascal triangle starts with 0 from top to bottom and elements in any particular row are numbered from left to right starting from 0.

Here is the formulae to find the value of n^{th} element of r^{th} row of pascal triangle.

## C program to print pascal triangle till N rows

#include <stdio.h> int getFactorial(int n); int main() { int row, rows, i, value; printf("Enter Number of Rows of Pascal Triangle\n"); scanf("%d", &rows); for(row = 0; row < rows; row++) { /* Print Spaces for every row */ for(i = row; i <= rows; i++) printf(" "); for(i = 0; i <= row; i++) { value = getFactorial(row)/(getFactorial(i)*getFactorial(row-i)); printf("%4d", value); } printf("\n"); } return 0; } /* * Function to calculate factorial of a number */ int getFactorial(int N){ if(N < 0){ printf("Invalid Input: factorial not defined for \ negative numbers\n"); return 0; } int nFactorial = 1, counter; /* N! = N*(N-1)*(N-2)*(N-3)*.....*3*2*1 */ for(counter = 1; counter <= N; counter++){ nFactorial = nFactorial * counter; } return nFactorial; }Output

Enter Number of Rows of Pascal Triangle 5 1 1 1 1 2 1 1 3 3 1 1 4 6 4 1

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