#include "OneButton.h"                              // Include the OneButton library
OneButton button(A0, true);                         // Attach a button on pin A0 to the library 

#define L1 2
#define L2 3
#define L3 4

int RLY1 = LOW;                                   
int RLY2 = LOW;
int RLY3 = LOW;

void setup() {
  pinMode(L1, OUTPUT);                              // Set the digital pin as output
  pinMode(L2, OUTPUT);                              // Set the digital pin as output
  pinMode(L3, OUTPUT);                              // Set the digital pin as output
  
  button.attachDoubleClick(doubleclick);            // Link the function to be called on a double-click event
  button.attachClick(singleclick);                  // Link the function to be called on a single-click event
  button.attachLongPressStop(longclick);            // Link the function to be called on a long-press event
} 
  
void loop() {
  button.tick();                                    // Check the status of the button
} 

void doubleclick() {                                // What happens when the button is double-clicked
  RLY1 = !RLY1;  
  digitalWrite(L1, RLY1);
}

void singleclick() {                                 // What happens when the button is clicked
  RLY2 = !RLY2;  
  digitalWrite(L2, RLY2);
}

void longclick() {                                   // What happens when the button is long-pressed
  RLY3 = !RLY3;  
  digitalWrite(L3, RLY3);
}