Example: Number Diamond in C

// Number Diamond
#include <stdio.h>

int main() {
    int n, i, j, k;

    // Step 1: Get user input for the number of rows (center width)
    printf("Enter the number of rows for the number diamond (odd number recommended): ");
    scanf("%d", &n);

    // Step 2: Print the upper half of the diamond
    for (i = 1; i <= n; i++) {
        // Print leading spaces
        for (j = 1; j <= n - i; j++) {
            printf(" ");
        }
        // Print increasing numbers
        for (j = 1; j <= i; j++) {
            printf("%d", j);
        }
        // Print decreasing numbers
        for (k = i - 1; k >= 1; k--) {
            printf("%d", k);
        }
        printf("\n");
    }

    // Step 3: Print the lower half of the diamond
    for (i = n - 1; i >= 1; i--) {
        // Print leading spaces
        for (j = 1; j <= n - i; j++) {
            printf(" ");
        }
        // Print increasing numbers
        for (j = 1; j <= i; j++) {
            printf("%d", j);
        }
        // Print decreasing numbers
        for (k = i - 1; k >= 1; k--) {
            printf("%d", k);
        }
        printf("\n");
    }

    return 0;
}