Home task 2-11

#include <stdio.h>



void genMatrix(unsigned **matrix, unsigned width, unsigned  height)
{
    unsigned blankW = width;
    unsigned blankH = height - 1;
    unsigned w = 0u;
    unsigned h = 0u;
    unsigned count = 0u;

    char route = 'r';   // r - right, d - down, l - left, u - up.

    while (blankW + blankH)
    {
        // Go to the right.
        for (unsigned i = 0; i < width - (width - blankW); ++i)
        {
            matrix[h][w] = ++count;
            ++w;
        }
        --w;
        --blankW;
        if (!blankH && !blankW) break;

        // Go to the down.
        ++h;
        for (unsigned i = 0; i < height - (height - blankH); ++i)
        {
            matrix[h][w] = ++count;
            ++h;
        }
        --h;
        --blankH;
        if (!blankH && !blankW) break;

        // Go to the left.
        --w;
        for (unsigned i = 0; i < width - (width - blankW); ++i)
        {
            matrix[h][w] = ++count;
            --w;
        }
        ++w;
        --blankW;
        if (!blankH && !blankW) break;

        // Go to the up.
        --h;
        for (unsigned i = 0; i < height - (height - blankH); ++i)
        {
            matrix[h][w] = ++count;
            --h;
        }
        --blankH;
        if (!blankH && !blankW) break;
        ++h;
        ++w;
    }
}



void printMatrix(unsigned **matrix, unsigned width, unsigned height)
{
    for (unsigned i = 0; i < height; ++i)
    {
        for (unsigned j = 0; j < width; ++j)
        {
            printf("%4d", matrix[i][j]);
        }
        puts("");
    }
}



int main()
{
    unsigned width, height;

    // Get user data.
    printf("Input matrix width: ");
    scanf_s("%u", &width);
    printf("Input matrix height: ");
    scanf_s("%u", &height);

    // Allocate memory.
    unsigned **matrix = (unsigned **)malloc(height * sizeof(unsigned *));
    for (unsigned i = 0; i < height; ++i)
    {
        matrix[i] = (unsigned *)malloc(width * sizeof(unsigned));
    }

    // Generate a matrix.
    genMatrix(matrix, width, height);

    // Draw a snail:)
    printMatrix(matrix, width, height);


    // Free
    for (unsigned i = 0; i < height; ++i)
    {
        free(matrix[i]);
    }
    free(matrix);

    return 0;
}