C program to print rhombus star pattern

• Write a C program to print rhombus star pattern using for loop.

For a rhombus star pattern of 6 rows. Program’s output should be:

Required Knowledge

• For Loop
• printf and scanf function in C

Algorithm to print rhombus star pattern using loop

• We first take the number of rows(N) as input from user using scanf function.
• The index of rows and columns will start from 0.
• Each row of rhombus star pattern contains N star characters.
• Each iteration of outer for loop(from i = 0 to N-1) will print one row of pattern at a time.
• Each j^th row, contains j space characters followed by N star characters.
• First inner for loop prints space characters whereas second inner for loop prints star characters.

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

 program to print rhombus 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++) {
        /* Print spaces before stars in a row */
        for (j = 0; j < i; j++) {
            printf(" ");
        }
        /* Print rows stars after spaces in a row */
        for (j = 0; j < rows; j++) {
            printf("*");
        }
        /* jump to next row */
        printf("\n");
    }
    return 0;
}

Output

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