Program to print a inverse pyramid character pattern
Last Updated :
20 Feb, 2023
Given a positive integer n, print the inverse pyramid pattern upto n rows as shown in the examples.
Examples :
Input : 4
Output :
A B C D D C B A
A B C C B A
A B B A
A A
Input : 6
Output :
A B C D E F F E D C B A
A B C D E E D C B A
A B C D D C B A
A B C C B A
A B B A
A A
Below is the implementation for the pattern:
C++
// C++ code to print inverse
// pyramid pattern
#include <bits/stdc++.h>
using namespace std;
// function to print the
// inverse pyramid pattern
void pyramid(int n)
{
int i, j, num, gap;
// outer loop to handle number
// of rows n in this case
for (i = n; i >= 1; i--) {
// inner loop to create right triangle
// gaps on left side of pyramid
for (gap = n - 1; gap >= i; gap--) {
cout<<" ";
cout<<" ";
}
// initializing value corresponding
// to 'A' ASCII value
num = 'A';
// loop to print characters on
// left side of pyramid
for (j = 1; j <= i; j++) {
cout << (char) num++ <<" ";
}
// loop to print characters on
// right side of pyramid
for (j = i - 1; j >= 0; j--) {
cout << (char) --num <<" ";
}
cout<<"\n";
}
}
// Driver function
int main()
{
int n = 9;
pyramid(n);
return 0;
}
// Java code for Inverse Pyramid
import java.util.*;
class GFG {
// function for inverse pyramid print
static void pyramid(int n)
{
int i, j, num, gap;
// outer loop to handle number
// of rows n in this case
for (i = n; i >= 1; i--) {
// inner loop to create right triangle
// gaps on left side of pyramid
for (gap = n - 1; gap >= i; gap--) {
System.out.print(" ");
System.out.print(" ");
}
// initializing value corresponding
// to ASCII value of 'A'
num = 'A';
// loop to print characters on
// left side of pyramid
for (j = 1; j <= i; j++) {
System.out.print((char)num++ + " ");
}
// loop to print characters on
// right side of pyramid
for (j = i - 1; j >= 0; j--) {
System.out.print((char)--num + " ");
}
System.out.println("");
}
}
/* Driver program to test above function */
public static void main(String[] args)
{
int n = 9;
pyramid(n);
}
}
//
# Python3 code to print inverse
# pyramid pattern
# function to print the following
# inverse pyramid pattern
def pyramid( n ):
# outer loop to handle number
# of rows n in this case
for i in range(n, 0, -1):
# inner loop to create right triangle
# gaps on left side of pyramid
for gap in range(n-1, i-1, -1):
print(" ", end = '')
print(" ", end = '')
# initializing value corresponding
# to 'A' ASCII value
num = ord('A')
# loop to print characters on
# left side of pyramid
for j in range(1, i+1):
print(chr(num), end = ' ')
num += 1
# loop to print characters on
# right side of pyramid
for j in range(i - 1, -1, -1):
num -= 1
print(chr(num), end = ' ')
print("\n", end = '')
# Driver Code
n = 9
pyramid(n)
# This code is contributed by "Sharad_Bhardwaj".
//C# code for Inverse Pyramid
using System;
class GFG {
// function for inverse pyramid print
static void pyramid(int n)
{
int i, j, num, gap;
// outer loop to handle number
// of rows n in this case
for (i = n; i >= 1; i--) {
// inner loop to create right triangle
// gaps on left side of pyramid
for (gap = n - 1; gap >= i; gap--) {
Console.Write(" ");
Console.Write(" ");
}
// initializing value corresponding
// to ASCII value of 'A'
num = 'A';
// loop to print characters on
// left side of pyramid
for (j = 1; j <= i; j++) {
Console.Write((char)num++ + " ");
}
// loop to print characters on
// right side of pyramid
for (j = i - 1; j >= 0; j--) {
Console.Write((char)--num + " ");
}
Console.WriteLine("");
}
}
/* Driver program to test above function */
public static void Main()
{
int n = 9;
pyramid(n);
}
}
// This article is contributed by vt_m.
<?php
// PHP implementation to print
// inverse pyramid pattern
// function to print the
// inverse pyramid pattern
function pyramid($n)
{
// outer loop to handle number
// of rows n in this case
for ($i = $n; $i >= 1; $i--)
{
// inner loop to create
// right triangle gaps on
// left side of pyramid
for ($gap = $n - 1; $gap >= $i;
$gap--)
{
echo" ";
}
// initializing value corresponding
// to 'A' ASCII value is 65
$num = 65;
// loop to print characters on
// left side of pyramid
for ($j = 1; $j <= $i; $j++)
{
echo chr($num++)." ";
}
// loop to print characters on
// right side of pyramid
for ($j = $i - 1; $j >= 0; $j--)
{
echo chr(--$num)." ";
}
echo"\n";
}
}
// Driver Code
$n = 9;
pyramid($n);
// This code is contributed by mits
?>
<script>
// JavaScript code to print inverse
// pyramid pattern
// function to print the
// inverse pyramid pattern
function pyramid(n)
{
var i, j, num, gap;
// outer loop to handle number
// of rows n in this case
for (i = n; i >= 1; i--) {
// inner loop to create right triangle
// gaps on left side of pyramid
for (gap = n - 1; gap >= i; gap--) {
document.write(" ");
}
// initializing value corresponding
// to 'A' ASCII value
num = "A".charCodeAt(0);
// loop to print characters on
// left side of pyramid
for (j = 1; j <= i; j++) {
document.write(String.fromCharCode(num++)
+ " ");
}
// loop to print characters on
// right side of pyramid
for (j = i - 1; j >= 0; j--) {
document.write(String.fromCharCode(--num)
+ " ");
}
document.write("<br>");
}
}
// Driver function
var n = 9;
pyramid(n);
</script>
OutputA B C D E F G H I I H G F E D C B A
A B C D E F G H H G F E D C B A
A B C D E F G G F E D C B A
A B C D E F F E D C B A
A B C D E E D C B A
A B C D D C B A
A B C C B A
A B B A
A A
Time Complexity: O(n2), where n represents the given input.
Auxiliary Space: O(1), no extra space is required, so it is a constant.