Right-Aligned Sequential Pyramid in C++

What You’ll Learn

Print letters in a running sequence (A, then B C, then D E F…) while keeping the triangle right-aligned by printing empty 2-column cells first. View output in a monospace terminal because alignment relies on fixed-width cells. Compare Program 13 (sequential, left-aligned) and Program 20 (right-aligned reverse). Includes a live preview, worked C++ examples, edge cases, and complexity.

📝 Problem & Approach

Given a row count n (or fixed 5), print a right-aligned pyramid of continuous alphabet letters in 2-column cells.

// Five rows (monospace; each cell is width 2)
//         A
//       B C
//     D E F
//   G H I J
// K L M N O

Inputs & Outputs

Minimal workflow

k = 'A'
for i in 1..n:
    for j from n down to 1:
        if j > i: print two spaces
        else: print k with width 2; k++
    print newline

Approach comparison

🔮 Live Preview

Choose between 1 and 6 rows and draw the right-aligned sequential pyramid in the browser (monospace cells).

Press "Draw pattern".

Examples Gallery

Three complete C++ programs — fixed 5 rows, user-chosen row count, and an explicit pad-then-letters rewrite. Click View Output to reveal sample console results.

#include <iostream>
#include <iomanip>
using namespace std;

int main() {
    char k = 'A';

    for (int i = 1; i <= 5; i++) {
        for (int j = 5; j >= 1; j--) {
            if (j > i)
                cout << "  ";
            else
                cout << setw(2) << k++;
        }
        cout << "\n";
    }

    return 0;
}

        A
      B C
    D E F
  G H I J
K L M N O

#include <iostream>
#include <iomanip>
using namespace std;

int main() {
    int n;
    char k = 'A';

    cout << "Enter number of rows (like 5): ";
    cin >> n;

    for (int i = 1; i <= n; i++) {
        for (int j = n; j >= 1; j--) {
            if (j > i)
                cout << "  ";
            else
                cout << setw(2) << k++;
        }
        cout << "\n";
    }

    return 0;
}

Enter number of rows (like 5): 3
    A
  B C
D E F

#include <iostream>
#include <iomanip>
using namespace std;

int main() {
    int n = 5;
    char k = 'A';

    for (int i = 1; i <= n; i++) {
        for (int s = 0; s < n - i; s++)
            cout << "  ";

        for (int L = 0; L < i; L++)
            cout << setw(2) << k++;

        cout << "\n";
    }

    return 0;
}

        A
      B C
    D E F
  G H I J
K L M N O

🔎 Worked Walkthrough — 5 rows

Trace each row’s pads, letters, and the running counter range.

Total letters: 1+2+3+4+5 = 15 (A through O). Each cell is 2 columns wide.

🎯 Practice Problems

Try these variations to lock in the pattern.

Notes

⏱️ Time and Space Complexity

Each of n rows scans n cells (or pads + letters totaling n), so total work is O(n²).

💡 Best Practices