C program to print right triangle star pattern

• Write a program in C to print right triangle star (*) pattern of n rows using for loop.
• Write a C program to print a right angles triangle pattern of star (*) character using loops.

For a right triangle star pattern of 7 rows. Program’s output should be:

Required Knowledge

• For Loop
• printf and scanf function in C

Algorithm to print right triangle star pattern using loop

• Take the number of rows(N) of right triangle as input from user using scanf function.
• Number of stars in K^th row is always K. 1^st row contains 1 star, 2^nd row contains 2 stars, 3^rd row contains 3 stars. In general, K^th row contains K stars.
• We will use two for loops to print right triangle star pattern.
• For a right triangle star pattern of N rows, outer for loop will iterate N time. Each iteration of outer loop will print one row of the pattern.
• For K^th row of right triangle pattern, inner loop will iterate K times. Each iteration of inner loop will print one star (*).

Here is the matrix representation of the triangle star pattern. The row numbers are represented by i whereas column numbers are represented by j.

C program to print right triangle star pattern

#include<stdio.h>
 
int main() {
    int i,j,rows;
    printf("Enter the number of rows\n");
    scanf("%d", &rows);
 
    for(i = 0; i < rows; i++) {
        /* Prints one row of triangle */
        for(j = 0; j <= i; ++j) {
           printf("* ");
        }
        /* move to next row */
        printf("\n");
    }
    return 0;
}

Output

Enter the number of rows
6
*
* *
* * *
* * * *
* * * * *
* * * * * *