Inverted Number Pyramid in C, C++, Java & Python – Code with Explanation & Examples in Short and Simple

   

C Program

#include <stdio.h>
int main() {
    int n=5;
    for(int i=n;i>=1;i--){
        for(int j=1;j<=i;j++) printf("%d ",j);
        printf("\n");
    }
}

C Output

Input:
5
Output:
1 2 3 4 5
1 2 3 4
1 2 3
1 2
1

C++ Program

#include <iostream>
using namespace std;
int main() {
    int n=6;
    for(int i=n;i>=1;i--){
        for(int j=1;j<=i;j++) cout<<j<<" ";
        cout<<"\n";
    }
}

C++ Output

Input:
6
Output:
1 2 3 4 5 6
1 2 3 4 5
1 2 3 4
1 2 3
1 2
1

JAVA Program

class Main {
    public static void main(String[] args) {
        int n=4;
        for(int i=n;i>=1;i--){
            for(int j=1;j<=i;j++) System.out.print(j+" ");
            System.out.println();
        }
    }
}

JAVA Output

Input:
4

Output:
1 2 3 4
1 2 3
1 2
1

Python Program

n=3
for i in range(n,0,-1):
    for j in range(1,i+1):
        print(j,end=" ")
    print()

Python Output

Input:
3
Output:
1 2 3
1 2
1

Deep-Dive, Extended Explanation

Understanding the Problem

The upside-down number pyramid is a deviation of the half pyramid shape in which the number of items goes down row by row. Rather than beginning with 1 and going up to n, in this case, we begin with n and go down to 1. This inversion reverses the direction of growth, producing a visually "upside-down" shape compared to the regular half pyramid.

Breaking Down the Logic

This pattern continues to employ nested loops, although the outer loop now counts in reverse. The inner loop prints from 1 up to the number of elements in the current row, determined by the counter for the outer loop.

If n=5:

Outer loop begins at 5 and decrements to 1.

1st row: prints 1 2 3 4 5

2nd row: prints 1 2 3 4

3rd row: prints 1 2 3

4th row: prints 1 2

5th row: prints 1

The only distinguishing factor from the standard half pyramid is running the outer loop in reverse.

Learning Insight

This illustrates:

How changing loop direction inverts output sequence.

How pattern shrinking in size can be controlled.

How outer loop variables determine row size.

Being proficient in this makes it simple to achieve:

Reverse sequences.

Staircase-like effects in games or UI.

Countdown-based number sequences.

Example

If you have 4 chocolate bars and you consume one less every day:

Day 1: 4 bars

Day 2: 3 bars

Day 3: 2 bars

Day 4: 1 bar

This is precisely how our pyramid gets smaller row by row.

Why It Matters

Loop reversal is essential in actual programming. It's applied in:

Sorting algorithms (reverse traversal).

Backward array iteration.

Descending order printing of data.

Object shrinking animations for games.

Programming Wisdom

In interview settings, this variation is frequently requested to test:

Whether you can re-use a known pattern by reversing loops.

Whether you are aware of loop boundaries and direction shifts.

If you can deliver tidy, trim code with no useless variables.

SEO-Optimized Closing

The inverted number pyramid pattern is a fundamental example in programming that demonstrates reverse iteration, nested loop control, and sequence shrinking. Whether you’re coding in C, C++, Java, or Python, this exercise strengthens your grasp on loop direction changes and builds problem-solving skills for pattern generation. It’s widely used in coding interviews, competitive programming, and real-world applications where data needs to be processed in reverse or progressively reduced.