Day 21 Nov 9

For the homework I had to create a quick sort function, and then use a quicksort function in a linked list. Here's a screenshot of both parts of the homework:

Just the quick list part
#include <stdio.h>
#include <stdlib.h>

//void quicksort(int[], int, int);
//int partition( int[], int, int);


int partition(int a[], int p, int r)
{
int i,j, pivot, temp;
pivot = a[p];
i = p;
j = r;
while(1)
{
while(a[i] < pivot && a[i] != pivot)
i++;
while(a[j] > pivot && a[j] != pivot)
j--;
if (i <j)
{
temp = a[i];
a[i] = a[j];
a[j] = temp;
}
else
{
return j;
}
}
}


void quicksort(int a[], int p, int r)
{
if (p < r)
{
int q;
q = partition(a, p ,r);
quicksort(a,p,q);
quicksort(a, q+1, r);
}
}




int main(void)
{
struct sort;

int a[]= {25, 52, 37, 63, 14, 17, 8, 6};

int i;


quicksort( a, 0, 7);

printf("Sorted array is: ");
for(i=0; i<8; ++i)
printf(" %d", a[i]);


return 0;

}

Here's a screenshot of the linked list working.

For lab we had to connect a speaker to an interrupter here's a video
here's the code


#include <TimerOne.h>

const int BUTTON_INT =0;
const int SPEAKER    =12;

#define NOTE_C 65
#define NOTE_D 73
#define NOTE_E 82
#define NOTE_F 87
#define NOTE_G 98
#define NOTE_A 110
#define NOTE_B 123

volatile int key = NOTE_C;
volatile int octave_multiplier = 1;
void setup()
{
  Serial.begin(9600);
  pinMode (SPEAKER, OUTPUT);
  attachInterrupt(BUTTON_INT, changeKey, RISING);

  Timer1.initialize(500000);
  Timer1.attachInterrupt(changePitch);
  // put your setup code here, to run once:


}
void changeKey()
{
  octave_multiplier =1;
  if (key ==NOTE_C)
  key = NOTE_D;
  else if(key == NOTE_D)
  key = NOTE_E;
  else if (key == NOTE_E)
  key = NOTE_F;
  else if (key == NOTE_F)
  key = NOTE_G;
  else if (key == NOTE_G)
  key = NOTE_A;
  else if (key ==NOTE_A)
  key = NOTE_B;
  else if (key == NOTE_B)
  key = NOTE_C;
}

void changePitch()
{
  octave_multiplier = octave_multiplier*2;
  if (octave_multiplier >16) octave_multiplier =1;
  tone(SPEAKER, key*octave_multiplier);
}


void loop()
{
  Serial.print("Key: ");
  Serial.print(key);
  Serial.print(" Multiplier: ");
  Serial.print(octave_multiplier);
  Serial.print(" Frequency: ");
  Serial.println(key*octave_multiplier);
  delay(100);
}// put your main code here, to run repeatedly: