int BUTTON1 = 26;
int BUTTON2 = 25;
int BUTTON3 = 33;
int BUTTON4 = 32;
int LED1 = 13;
int LED2 = 12;
int LED3 = 14;
int LED4 = 27;
int LED1state=0;
int LED2state=0;
int LED3state=0;
int LED4state=0;
int BUTTON1new;
int BUTTON2new;
int BUTTON3new;
int BUTTON4new;
int BUTTON1old=0;
int BUTTON2old=0;
int BUTTON3old=0;
int BUTTON4old=0;

void setup() {
  pinMode(BUTTON1,INPUT);
  pinMode(BUTTON2,INPUT);
  pinMode(BUTTON3,INPUT);
  pinMode(BUTTON4,INPUT);
  pinMode(LED1,OUTPUT);
  pinMode(LED2,OUTPUT);
  pinMode(LED3,OUTPUT);
  pinMode(LED4,OUTPUT);
  Serial.begin(9600);
  Serial.print("hi");
}

void loop() {
  
  
  BUTTON1new=digitalRead(BUTTON1);
  if(BUTTON1new==1 && BUTTON1old== 0){
    if(LED1state==0){
      digitalWrite(LED1,1);
      LED1state=1;
    }
    else{
      digitalWrite(LED1,0);
      LED1state=0;
    }
 }
  BUTTON1old=BUTTON1new;
  delay(100);
  
  BUTTON2new=digitalRead(BUTTON2);
  if(BUTTON2new==1 && BUTTON2old== 0){
    if(LED2state==0){
      digitalWrite(LED2,1);
      LED2state=1;
    }
    else{
      digitalWrite(LED2,0);
      LED2state=0;
    }
 }
  BUTTON2old=BUTTON2new;
  delay(100);
  
  BUTTON3new=digitalRead(BUTTON3);
  if(BUTTON3new==1 && BUTTON3old== 0){
    if(LED3state==0){
      digitalWrite(LED3,1);
      LED3state=1;
    }
    else{
      digitalWrite(LED3,0);
      LED3state=0;
    }
 }
  BUTTON3old=BUTTON3new;
  delay(100);
  
  BUTTON4new=digitalRead(BUTTON4);
  if(BUTTON4new==1 && BUTTON4old== 0){
    if(LED4state==0){
      digitalWrite(LED4,1);
      LED4state=1;
    }
    else{
      digitalWrite(LED4,0);
      LED4state=0;
    }
 }
  BUTTON4old=BUTTON4new;
  delay(100);
  

    if(Serial.available()){
    char home=Serial.read();
    if(home=='a'){
      digitalWrite(LED1,1);
    }
    else if(home=='b'){
      digitalWrite(LED2,1); 
    }
    else if(home=='c'){
      digitalWrite(LED3,1);
    }
    else if(home=='d'){
      digitalWrite(LED4,1);
    }
    else if(home=='e'){
      digitalWrite(LED1,1);
      digitalWrite(LED2,1);
      digitalWrite(LED3,1);
      digitalWrite(LED4,1);
    }
    else if(home=='f'){
      digitalWrite(LED1,0);
      digitalWrite(LED2,0);
      digitalWrite(LED3,0);
      digitalWrite(LED4,0);
    }
    else if(home=='g'){
      digitalWrite(LED1,0);
    }
    else if(home=='h'){
      digitalWrite(LED2,0);
    }
    else if(home=='i'){
      digitalWrite(LED3,0);
    }
    else if(home=='j'){
      digitalWrite(LED4,0);
    }
  }
  
}