Write a program in C to print print palindrome triangle pattern of n rows.
How to print a right triangle of palindrome strings using for loops.
Palindrome triangle pattern of 5 rows:
A
ABA
ABCBA
ABCDCBA
ABCDEDCBA
Required Knowledge
For Loop
If Else Statement
printf and scanf function in C
Algorithm to print triangle pattern of palindrome strings
This program is similar to right triangle star pattern program.
Take the number of rows(N) of right triangle as input from user using scanf function.
Number of characters in Kth row is always 2K-1. 1st row contains 1 character, 2nd row contains 3 characters, 3rd row contains 5 characters and so on.
In any row, we will first print the characters in increasing order of their ASCII value till mid of the row and then in decreasing order.
We will use two for loops to print right triangle of palindrome strings.
Outer for loop will iterate N time. Each iteration of outer loop will print one row of the pattern.
Each iteration of inner loop will print a palindrome string as explained above.
C program to print palindrome triangle pattern
#include<stdio.h>
int main() {
int i, j, rows, count=0;
printf("Enter the number of rows\n");
scanf("%d", &rows);
for (i = 1; i <= 2*rows; i=i+2)
{
for (j = 1; j <= i; j++)
{
printf("%c", 'A'+count);
if(j <= i/2)
count++;
else
count--;
}
count = 0;
printf("\n");
}
return(0);
}
Output
Enter the number of rows
5
A
ABA
ABCBA
ABCDCBA
ABCDEDCBA
