Table of Contents
C program to generate pascal triangle using Array
In this tutorial, we will discuss the C program to generate a pascal triangle using an Array
In this post, we are going to learn how to display the pascal triangle pattern in C language using for, while, and do-while loop

C program to print pascal triangle
Program to display pascal triangle Using for loop
Program 1
in this program, the user declares and initializes some variables as integers and then the program will display the pascal triangle number pattern using for loop in C language
#include <stdio.h>
#include <stdlib.h>
int main()
{
int arr[30],arrTemp[30];
//declare two one dim arrays
int i,j,k,l, rowNo=6;
//declare and initialize
arrTemp[0]=1;
arr[0]=1;
//initialize array elements
for(j=0; j<rowNo; j++)
printf(" ");
printf(" 1\n");
for(i=1; i<rowNo; i++){
for(j=0; j<i; j++)
printf(" ");
for(k=1; k<=rowNo; k++){
arr[k]=arrTemp[k-1]+arrTemp[k];
}
arr[i]=1;
for(l=0; l<=i; l++){
printf("%3d",arr[l]);
arrTemp[l]=arr[l];
}
printf("\n");
}
getch();
return 0;
}
When the above code is executed, it produces the following result

Program to display pascal triangle Using for loop with user input
Program 2
This program allows the user to enter the number of rows, and it will display the pascal triangle number pattern using for loop in C language according to the rows
#include <stdio.h>
#include <stdlib.h>
int main()
{
int arrOne[30],arrTemp[30];//Declare single dim arrays
int i,j,k,l, rowNum;//declare variables
printf("Enter the Number o rows : ");
//ask input
scanf("%d",&rowNum);
//Reading the input
arrTemp[0]=1;//initialize Single dim temp array index 0
arrOne[0]=1;//initialize Single dim array index 0
for(j=0; j<rowNum; j++)
printf(" ");//print space
printf(" 1\n");
for(i=1; i<rowNum; i++){
for(j=0; j<i; j++)
printf(" ");
//print space
for(k=1; k<=rowNum; k++){
arrOne[k]=arrTemp[k-1]+arrTemp[k];
}//print numbers
arrOne[i]=1;
for(l=0; l<=i; l++){
printf("%3d",arrOne[l]);
arrTemp[l]=arrOne[l];
}
printf("\n");
//move to next line
}
getch();
return 0;
}
When the above code is executed, it produces the following result
Enter the Number o rows :3

Program to display pascal triangle Using while loop
Program 3
in this program , the user declares and initializes some variables as integer and then the program will display the pascal triangle number pattern using while loop in C language
#include <stdio.h>
#include <stdlib.h>
int main()
{
int arr[30],arrTemp[30];
//declare two one dim arrays
int i,j,k,l, numRow=4;
//declare and initialize
//printf("Enter the number of rows: ");
//scanf("%d",&num_Row);
arrTemp[0]=1;
arr[0]=1;
//initialize array elements
j=0;
while(j<numRow){
printf(" ");
j++;
}
printf(" 1\n");
i=1;
while(i<numRow){
j=0;
while(j<i){
printf(" ");
j++;
}
k=1;
while(k<=numRow){
arr[k]=arrTemp[k-1]+arrTemp[k];
k++;
}
arr[i]=1;
l=0;
while(l<=i){
printf("%3d",arr[l]);
arrTemp[l]=arr[l];
l++;
}
printf("\n");
i++;
}
getch();
return 0;
}
When the above code is executed, it produces the following result

Program to display pascal triangle Using while loop with user input
Program 4
This program allows the user to enter the number of rows and it will display the pascal triangle number pattern using while loop in C language according to the rows
#include <stdio.h>
#include <stdlib.h>
int main()
{
int arr[30],arrTemp[30];
//declare two one dim arrays
int i,j,k,l, numRow;
//declare and initialize
printf("Enter the value for the number of rows: ");
scanf("%d",&numRow);
arrTemp[0]=1;
arr[0]=1;
//initialize array elements
j=0;
while(j<numRow){
printf(" ");
j++;
}
printf(" 1\n");
i=1;
while(i<numRow){
j=0;
while(j<i){
printf(" ");
j++;
}
k=1;
while(k<=numRow){
arr[k]=arrTemp[k-1]+arrTemp[k];
k++;
}
arr[i]=1;
l=0;
while(l<=i){
printf("%3d",arr[l]);
arrTemp[l]=arr[l];
l++;
}
printf("\n");
i++;
}
getch();
return 0;
}
When the above code is executed, it produces the following result
Enter the value for the number of rows: 5

Program to display pascal triangle Using do-while loop
Program 5
in this program , the user declares and initializes some variables as integers and then the program will display the pascal triangle number pattern using do-while loop in Java language
#include <stdio.h>
#include <stdlib.h>
int main()
{
int arr[30],arrTemp[30];
//declare two one dim arrays
int i,j,k,l, rowNum=5;
//declare and initialize variables
arrTemp[0]=1;
arr[0]=1;
//initialize elements o an array to 0 index
j=0;
do{
printf(" ");
j++;
} while(j<rowNum);
printf(" 1\n");
i=1;
do{
for(j=0; j<i; j++)
printf(" ");
k=1;
while(k<=rowNum){
arr[k]=arrTemp[k-1]+arrTemp[k];
k++;
}
arr[i]=1;
l=0;
do{
printf("%3d",arr[l]);
arrTemp[l]=arr[l];
l++;
} while(l<=i);
printf("\n");
i++;
}while(i<rowNum);
getch();
return 0;
}
When the above code is executed, it produces the following result

Program to display pascal triangle Using do-while loop with user input
Program 6
This program allows the user to enter the number of rows, and it will display the pascal triangle number pattern using do-while loop in C language according to the rows
#include <stdio.h>
#include <stdlib.h>
int main()
{
int arr[30],arrTemp[30];
//declare two one dim arrays
int i,j,k,l, rowNo;
//declare and variables
printf("Enter the value for the number of rows: ");
//ask input from user
scanf("%d",&rowNo);
//read the input
arrTemp[0]=1;
arr[0]=1;
//initialize array elements as 1
j=0;
do{
printf(" ");
j++;
} while(j<rowNo);
printf(" 1\n");
i=1;
do{//outter do-while
for(j=0; j<i; j++)
printf(" ");
k=1;
while(k<=rowNo){
arr[k]=arrTemp[k-1]+arrTemp[k];
k++;
}
arr[i]=1;
l=0;
do{//inner do-while
printf("%3d",arr[l]);
arrTemp[l]=arr[l];
l++;
} while(l<=i);
printf("\n");
i++;
}while(i<rowNo);
getch();
return 0;
}
When the above code is executed, it produces the following result
Enter the value for the number of rows: 5

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