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   cls();
   puts("foobar!");

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#include "system.h"

unsigned short *videomem = (unsigned short *)0xB8000;;
unsigned int cursor_x = 0, cursor_y = 0;
unsigned char color = 0x0F, clearcolor = 0x0F;

void update_cursor()
{
    unsigned temp;

    /* The equation for finding the index in a linear
    *  chunk of memory can be represented by:
    *  Index = [(y * width) + x] */
    temp = cursor_y * 80 + cursor_x;

    /* This sends a command to indicies 14 and 15 in the
    *  CRT Control Register of the VGA controller. These
    *  are the high and low bytes of the index that show
    *  where the hardware cursor is to be 'blinking'. To
    *  learn more, you should look up some VGA specific
    *  programming documents. A great start to graphics:
    *  http://www.brackeen.com/home/vga */
    outportb(0x3D4, 14);
    outportb(0x3D5, temp >> 8);
    outportb(0x3D4, 15);
    outportb(0x3D5, temp);
}

// Clears the screen
void cls() {
   unsigned short blank = 0x20 | (clearcolor << 8);   // A blank character
   int i;
   for(i = 0; i < 25; i++)            // Loop through all rows
      memsetw(videomem + i*80, blank, 80);   // Clear one row
   cursor_x = 0;   // Move the cursor
   cursor_y = 0;
   update_cursor();
}

// These functions set your output color. Top four bytes are background, last for are foreground (text) color
void setClearColor(int fg, int bg) {
   clearcolor = (bg << 4) | (fg & 0x0F);
}

void setColor(int fg, int bg) {
   color = (bg << 4) | (fg & 0x0F);
}

void scroll(){
   if(cursor_y > 24) {
      unsigned short blank = 0x20 | (clearcolor << 8);   // A blank character   
      memcpy(videomem, videomem + 80, 80 * 24);
      memsetw(videomem + 24*80, blank, 80);
      cursor_y = 24;
      update_cursor();
   }
}

void putch(unsigned char c) {
   unsigned short *where = videomem + (80 * cursor_y + cursor_x);
   if(c == '\b') {   // Backspace character, clear the previous character if we're not at the beginning of the line
      if(cursor_x != 0) {
         cursor_x--;
         *where = 0x20 | (clearcolor << 8);
      }
   } else if (c == '\t') {   // A tab character, move the cursor to a point where cursor_x is divisible by 8
      cursor_x = (cursor_x + 8) & ~(8 - 1);
      if(cursor_x >= 79) { // end of line
         cursor_x = 7;
         cursor_y++;
         scroll();
      }
   } else if (c == '\n') {   // Newline, go to the beginning of the next line.
      cursor_x = 0;
      cursor_y++;
      scroll();
   } else if (c == '\r') {
      cursor_x = 0;
   } else if (c >= ' ') {
      *where = c | (color << 8);
      
      if(cursor_x >= 79) {
         cursor_x = 0;
         cursor_y++;
         scroll();
      } else {
         cursor_x++;
      }
   }
   update_cursor();
}

void puts(unsigned char *text) {
   int i;
   for(i = 0; i < strlen(text); i++)
      putch(text[i]);
}

void initvga() {
   videomem = (unsigned short *)0xB8000;
   cls();
}

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   for(i = 0; i < 25; i++)            // Loop through all rows
      memsetw(videomem + i*80, blank, 80);   // Clear one row

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   for(i = 0; i < 25; i++)            // Loop through all rows
      memsetw(videomem + i*160, blank, 80);   // Clear one row

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   unsigned short *where = videomem + (80 * cursor_y + cursor_x);

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   unsigned short *where = videomem + (160 * cursor_y + cursor_x);

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#include <stdio.h>

int main()
{
   int intArr[] = { 1, 2, 3, 4 }; /* Each number is 4bytes */
   int *ptr = intArr;
   ++ptr;
   printf("%d\n", *ptr);
   ptr += 1;
   printf("%d\n", *ptr);
   ptr = ptr + 1;
   printf("%d\n", *ptr);

   return 0;
}

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memsetw(videomem + i*80, blank, 80);

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memsetw(videomem + i*80, blank, 80);

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memsetw(
(unsigned short*) ( (uintptr_t)videomem + ( i * 80 * sizeof(unsigned short) ) ),
blank, 80);