C Program to Print Right-Angled Triangle Pattern

Introduction

Printing a right-angled triangle pattern is a simple and common exercise for beginners in C programming. It helps in understanding how to use nested loops and handle formatting.

Problem Statement

Create a C program that:

• Accepts the number of rows for the triangle.
• Prints a right-angled triangle using stars (*).

Example:

• Input: rows = 5
• Output:

  *
  **
  ***
  ****
  *****
  

Solution Steps

1. Input the Number of Rows: The size determines how many rows the triangle will have.
2. Use Nested Loops: The outer loop controls the number of rows, while the inner loop controls the number of stars printed for each row.
3. Display the Right-Angled Triangle: Print stars in increasing order row by row.

C Program

#include <stdio.h>

int main() {
    int i, j, rows;

    // Step 1: Accept the number of rows for the triangle
    printf("Enter the number of rows: ");
    scanf("%d", &rows);

    // Step 2: Outer loop for the rows
    for (i = 1; i <= rows; i++) {
        // Step 3: Inner loop to print stars
        for (j = 1; j <= i; j++) {
            printf("*");
        }

        // Move to the next line after each row
        printf("\n");
    }

    return 0;
}

Explanation

Step 1: Input Number of Rows

• The program starts by taking input from the user to determine the number of rows for the triangle.

Step 2: Outer Loop for Rows

• The outer loop controls the number of rows printed. It runs from 1 to the number of rows specified by the user.

Step 3: Inner Loop for Stars

• The inner loop prints the number of stars (*) in each row. The number of stars printed corresponds to the current row number, increasing by one star for each subsequent row.

Output Example

For rows = 5, the output will be:

*
**
***
****
*****

For rows = 7, the output will be:

*
**
***
****
*****
******
*******

Conclusion

This C program prints a right-angled triangle using stars (*). The number of stars increases with each row, creating the triangle shape. This exercise is helpful for beginners to practice using loops in C.