void setup() {
  // put your setup code here, to run once:
for(int i=2;i<10;i++)
    pinMode(i, OUTPUT);

pinMode(A5, INPUT_PULLUP);

}
int on=0;
int ba5;
void loop() {
  // put your main code here, to run repeatedly:
if(digitalRead(A5)==0&&ba5==1)   on=(on+1)%2;
  
   ba5=digitalRead(A5);
    delay(2);
     
    

switch(on)
{
  case 0:for(int i=2;i<=5;i++)
  {
    digitalWrite(i, HIGH);
    if(digitalRead(A5)==0&&ba5==1)   on=(on+1)%2;
 
   ba5=digitalRead(A5);
   delay(2);

  }
            if(digitalRead(A5)==0&&ba5==1)   on=(on+1)%2;
  
   ba5=digitalRead(A5);
   
  for(int i=6;i<=9;i++)
  {
     digitalWrite(i, LOW);
if(digitalRead(A5)==0&&ba5==1)   on=(on+1)%2;
  
   ba5=digitalRead(A5);
    delay(2);
   }
            
  break;
  case 1:for(int i=2;i<=5;i++)
  {
    digitalWrite(i, 0);
if(digitalRead(A5)==0&&ba5==1)   on=(on+1)%2;
   
   ba5=digitalRead(A5);
    delay(2);
  }
  if(digitalRead(A5)==0&&ba5==1)   on=(on+1)%2;
   
   ba5=digitalRead(A5);
    delay(2);
            
  for(int i=6;i<=9;i++)
  {
     digitalWrite(i, 1);
if(digitalRead(A5)==0&&ba5==1)   on=(on+1)%2;
   
   ba5=digitalRead(A5);
    delay(2);
   }
  break; 
}



/*for(int i=2;i<=9;i++)
{
 digitalWrite(i, HIGH);  
      delay(250);
      digitalWrite(i, LOW);
}
  for(int i=8;i>2;i--)
  {
    digitalWrite(i, HIGH);  
      delay(250);
      digitalWrite(i, LOW);
      
  }*/

}