#define RelayPin1 21
#define RelayPin2 19
#define RelayPin3 32
#define RelayPin4 33
#define SwitchPin1 25
#define SwitchPin2 26
#define SwitchPin3 27
#define SwitchPin4 14

int toggleState_1 = 0; //Define integer to remember the toggle state for relay 1
int toggleState_2 = 0; //Define integer to remember the toggle state for relay 2
int toggleState_3 = 0; //Define integer to remember the toggle state for relay 3
int toggleState_4 = 0; //Define integer to remember the toggle state for relay 4
 String re;
 int relay;
 String position;
 int buttonstate1;
 int buttonstate2;
 int buttonstate3;
 int buttonstate4;
void setup()
{
  Serial.begin(9600);
  pinMode(RelayPin1, OUTPUT);
  pinMode(RelayPin2, OUTPUT);
  pinMode(RelayPin3, OUTPUT);
  pinMode(RelayPin4, OUTPUT);

  pinMode(SwitchPin1, INPUT);
  pinMode(SwitchPin2, INPUT);
  pinMode(SwitchPin3, INPUT);
  pinMode(SwitchPin4, INPUT);

  digitalWrite(RelayPin1, toggleState_1);
  digitalWrite(RelayPin2, toggleState_2);
  digitalWrite(RelayPin3, toggleState_3);
  digitalWrite(RelayPin4, toggleState_4);


}
void loop()
{

buttonstate1=digitalRead(SwitchPin1);

if(buttonstate1==HIGH)
{
  digitalWrite(RelayPin1,HIGH);
  delay(1000);
}
else
{
  digitalWrite(RelayPin1,LOW);
  delay(1000);
}
buttonstate2=digitalRead(SwitchPin2);

if(buttonstate2==HIGH)
{
  digitalWrite(RelayPin2,HIGH);
  delay(1000);
}
else
{
  digitalWrite(RelayPin2,LOW);
  delay(1000);
}
buttonstate3=digitalRead(SwitchPin3);

if(buttonstate3==HIGH)
{
  digitalWrite(RelayPin3,HIGH);
  delay(1000);
}
else
{
  digitalWrite(RelayPin3,LOW);
  delay(1000);
}
buttonstate4=digitalRead(SwitchPin4);

if(buttonstate4==HIGH)
{
  digitalWrite(RelayPin4,HIGH);
  delay(1000);
}
else
{
  digitalWrite(RelayPin4,LOW);
  delay(1000);
}
}
  Serial.println("Which light you want to turn on/off?");
  delay(5000);
  while(Serial.available()==0){}
  re=Serial.readString();
  relay= re.toInt();
  {
    switch(relay){
      case 1: 
             if(toggleState_1 == 0){
              digitalWrite(RelayPin1, HIGH); // turn on relay 1
              toggleState_1 = 1;
              Serial.println("Device1 ON");
              }
             else{
              digitalWrite(RelayPin1, LOW); // turn off relay 1
              toggleState_1 = 0;
              Serial.println("Device1 OFF");
              }
             delay(1000);
      break;
      case 2: 
             if(toggleState_2 == 0){
              digitalWrite(RelayPin2, HIGH); // turn on relay 2
              toggleState_2 = 1;
              Serial.println("Device2 ON");
              }
             else{
              digitalWrite(RelayPin2, LOW); // turn off relay 2
              toggleState_2 = 0;
              Serial.println("Device2 OFF");
              }
             delay(1000);
      break;
      case 3: 
             if(toggleState_3 == 0){
              digitalWrite(RelayPin3, HIGH); // turn on relay 3
              toggleState_3 = 1;
              Serial.println("Device3 ON");
              }
             else{
              digitalWrite(RelayPin3, LOW); // turn off relay 3
              toggleState_3 = 0;
              Serial.println("Device3 OFF");
              }
             delay(1000);
      break;
      case 4: 
             if(toggleState_4 == 0){
              digitalWrite(RelayPin4, HIGH); // turn on relay 4
              toggleState_4 = 1;
              Serial.println("Device4 ON");
              }
             else{
              digitalWrite(RelayPin4, LOW); // turn off relay 4
              toggleState_4 = 0;
              Serial.println("Device4 OFF");
              }
             delay(1000);
      break;}
  }