Palindrome triangle

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