volatile bool switch1_state = false;
volatile bool switch2_state = false;
volatile bool switch3_state = false;
volatile bool switch4_state = false;
void setup() {
  // put your setup code here, to run once:
DDRF|=0xFF;//setting all pins to output
DDRK|=0x00;
PORTK|=0x00;//setting up pull down 
}
void switch_1(){
   volatile char *pin;
  pin = 0x106; // Address of PIN register for PORTK
  volatile char x;
  x = *pin;
  if (x&(1<<PK0)) {
    switch1_state = true;  // Set the state to "on"
  }
  if (switch1_state) {
    PORTF|=0xFF;
  }
}
void switch_2(){
// put your main code here, to run repeatedly:
  volatile char *pin;
  pin=0x106;
  volatile char x;
  x=*pin;
  if(x&(1<<PK1)){
    PORTF^=0xFF;
    delay(500);
  }
  else{
    PORTF=0x00;
  }
}
void switch_3(){
volatile char *pin,x;
pin=0x106;
x=*pin;
volatile char *out;
out=0x31;
int i;
for(i=0;i<8;i++){
  if(x&(1<<PK2)){
   *out=(1<<i);
   delay(500);
  }
}
}
void switch_4(){
  volatile char *pin,x;
pin=0x106;
x=*pin;
volatile char *out;
out=0x31;
int i;
for(i=7;i>=0;i--){
  if(x&(1<<PK3)){
   *out=(1<<i);
   delay(500);
  }
}
}
void switch_5(){
volatile char *pin,x;
pin=0x106;
x=*pin;
volatile char *out;
out=0x31;
if(x&(1<<PK4)){
  *out=(1<<3)|(1<<5)|(1<<7);
}
}
void switch_6(){
volatile char *pin,x;
pin=0x106;
x=*pin;
volatile char *out;
out=0x31;
if(x&(1<<PK5)){
  switch2_state=true;
}
if(switch2_state){
    *out|=(1<<5);
}
if(x&(1<<PK6)){
  switch3_state=true;
}
if(switch3_state){
   *out|=(1<<6);
}
if(x&(1<<PK7)){
 switch4_state=true;
}
if(switch4_state){
  *out|=(1<<7);
}
}
void loop() {
 switch_1();
 switch_2();
 switch_3();
 switch_4();
 switch_5();
 switch_6();
}