Number pattern 44 in C

1
3  2
4  5  6
10 9  8  7
11 12 13 14 15

Required knowledge

Logic to print the given pattern

1
3  2
4  5  6
10 9  8  7
11 12 13 14 15

1. The pattern contains N rows (where N is the total number of rows to be printed).
2. Each row contains exactly i columns (where i is the current row number).
3. Now, talking about the numbers printed. They are printed in a special order i.e. for each odd row numbers are printed in ascending order and for even rows they are printed in descending order.
4. For odd row first column value start at total_numbers_printed + 1 (where total_numbers_printed is the total numbers printed till current row, column).
5. For even row first column value start at total_numbers_printed + i.

Program to print the given pattern

/**
 * C program to print the given number pattern
 */

#include <stdio.h>

int main()
{
    int i, j, count, value, N;

    printf("Enter rows: ");
    scanf("%d", &N);

    count = 0;

    for(i=1; i<=N; i++)
    {
        // Starting value of column based on even or odd row.
        value = (i & 1) ? (count + 1) : (count + i);

        for(j=1; j<=i; j++)
        {
            printf("%-3d", value);

            // Increment the value for odd rows
            if(i & 1)
                value++;
            else
                value--;

            count++;
        }

        printf("\n");
    }

    return 0;
}

Screenshot