(using if, if-else, nested if, switch-case)

(using for, while, do-while loops)

C Programs

Share with a Friend

Print Number Diamond Pattern

Introduction

The Number Diamond Pattern is a symmetrical pattern formed by combining a number pyramid and its inverted reflection.
It displays numbers increasing from 1 up to the row count and then decreasing back symmetrically.

For example, for n = 5:

1 2

1 2 3

1 2 3 4

1 2 3 4 5

1 2 3 4

1 2 3

1 2

This program is excellent for mastering nested loops and mirror pattern logic.

C Program: Print Number Diamond Pattern

Method 1: Using for loop

#include <stdio.h>
 
int main() {
    int n;
    printf("Enter number of rows: ");
    scanf("%d", &n);
 
    // Upper half (pyramid)
    for (int i = 1; i <= n; i++) {
        for (int j = i; j < n; j++)
            printf(" ");
        for (int k = 1; k <= i; k++)
            printf("%d ", k);
        printf("\n");
    }
 
    // Lower half (inverted pyramid)
    for (int i = n - 1; i >= 1; i--) {
        for (int j = n; j > i; j--)
            printf(" ");
        for (int k = 1; k <= i; k++)
            printf("%d ", k);
        printf("\n");
    }
 
    return 0;
}

Output

 
OUTPUT :
Enter number of rows: 5
    1
   1 2
  1 2 3
 1 2 3 4
1 2 3 4 5
 1 2 3 4
  1 2 3
   1 2
    1

Explanation

The first loop block prints the upper pyramid (1 to n).
The second loop block prints the inverted pyramid (n–1 to 1).
Each part uses nested loops:
- One for spaces (alignment)
- One for numbers (1 to current row number)

C Program: Print Number Diamond Pattern

Method 2: Using while loop

#include <stdio.h>
 
int main() {
    int n, i, j, k;
    printf("Enter number of rows: ");
    scanf("%d", &n);
 
    i = 1;
    // Upper half
    while (i <= n) {
        j = i;
        while (j < n) {
            printf(" ");
            j++;
        }
 
        k = 1;
        while (k <= i) {
            printf("%d ", k);
            k++;
        }
 
        printf("\n");
        i++;
    }
 
    i = n - 1;
    // Lower half
    while (i >= 1) {
        j = n;
        while (j > i) {
            printf(" ");
            j--;
        }
 
        k = 1;
        while (k <= i) {
            printf("%d ", k);
            k++;
        }
 
        printf("\n");
        i--;
    }
 
    return 0;
}

Output

 
OUTPUT :
Enter number of rows: 5
    1
   1 2
  1 2 3
 1 2 3 4
1 2 3 4 5
 1 2 3 4
  1 2 3
   1 2
    1

Explanation

The first loop block prints the upper pyramid (1 to n).
The second loop block prints the inverted pyramid (n–1 to 1).
Each part uses nested loops:
- One for spaces (alignment)
- One for numbers (1 to current row number)

C Program: Print Number Diamond Pattern

Method 3: Using do..while loop

#include <stdio.h>
 
int main() {
    int n, i, j, k;
    printf("Enter number of rows: ");
    scanf("%d", &n);
 
    i = 1;
    // Upper half
    do {
        j = i;
        do {
            if (j < n)
                printf(" ");
            j++;
        } while (j <= n);
 
        k = 1;
        do {
            if (k <= i)
                printf("%d ", k);
            k++;
        } while (k <= i);
 
        printf("\n");
        i++;
    } while (i <= n);
 
    i = n - 1;
    // Lower half
    do {
        j = n;
        do {
            if (j > i)
                printf(" ");
            j--;
        } while (j >= i);
 
        k = 1;
        do {
            if (k <= i)
                printf("%d ", k);
            k++;
        } while (k <= i);
 
        printf("\n");
        i--;
    } while (i >= 1);
 
    return 0;
}

Output

 
OUTPUT :
Enter number of rows: 5
    1
   1 2
  1 2 3
 1 2 3 4
1 2 3 4 5
 1 2 3 4
  1 2 3
   1 2
    1

Explanation

The first loop block prints the upper pyramid (1 to n).
The second loop block prints the inverted pyramid (n–1 to 1).
Each part uses nested loops:
- One for spaces (alignment)
- One for numbers (1 to current row number)

Basics of C Programming (Introductory Programs)

Control Statements & Loops in C

Functions

Arrays

Strings

Pointers

Structures and Unions

Dynamic Memory Allocation

File Handling

Data Structures in C

Advanced C Programs

User-Defined Number Programs in C

User-Defined String Programs in C

C Programs

Share with a Friend

Loop Programs in C

Print Number Diamond Pattern

Introduction

C Program: Print Number Diamond Pattern

Method 1: Using for loop

Output

Explanation

C Program: Print Number Diamond Pattern

Method 2: Using while loop

Output

Explanation

C Program: Print Number Diamond Pattern

Method 3: Using do..while loop

Output

Explanation