Automatic Arduino Goal Counter for Table Football/Soccer

/* 
  Code for automatic table soccer counter. By teacher Morgenthaler and student Leo at Swiss school www.oszt.ch
*/
                                           
// 3 lines importing libraries for the Adafruit display 
#include <Wire.h>                                 
#include <Adafruit_GFX.h>                         
#include "Adafruit_LEDBackpack.h"

// Initailizing the 7-segment display 
Adafruit_7segment matrix = Adafruit_7segment();   

// Defining varialbes for the two goals
int Rot;                                          
int Blau;

// Defining Arduino's board-LED. For controlling purpose only during coding
#define LEDPIN 13                                 
                                                 
// Defining the two pins the data connections of the breakbeam sensors 
#define SENSORPIN 4                               
#define SENSORPIN2 2  

// Defining the pin for the back to zero button                            
#define SENSORPIN3 7                              

 // Initalizing and defining states for the breakbeam sensors and the back to zero button 
int sensorState = 0, lastState=0;               
int sensorState2 = 0, lastState2=0;              
int sensorState3 = 0, lastState3=0;              
                                                 
void setup() {        
                              
  // Initializing Arduino's board LED for output                                                
  pinMode(LEDPIN, OUTPUT);                        
                                                  
  // Initializing pin for input from breakbeam sensor                                               
  pinMode(SENSORPIN, INPUT);  
  // Activating the pullup resistor for this pin to make the two sensor states clear for Arduino                    
  digitalWrite(SENSORPIN, HIGH);                  

  // Same for other breakbeam sensor
  pinMode(SENSORPIN2, INPUT);                     
  digitalWrite(SENSORPIN2, HIGH);

  // Same for back to zero button
  pinMode(SENSORPIN3, INPUT);                     
  digitalWrite(SENSORPIN3, HIGH);

  // Start value for goals
  Rot = 0;                                         
  Blau = 0;

  //Define address for display
  matrix.begin(0x70);                              
}



void loop(){                                      
  // Next 3 lines: Read and save states of the 2 sensors and the back to zero button                                               
  sensorState = digitalRead(SENSORPIN);           
  sensorState2 = digitalRead(SENSORPIN2);
  sensorState3 = digitalRead(SENSORPIN3);         

  
  // The following lines are for displaying the the goal values on the display.
  // This if argument prevents from displaying a zero with numbers under 10
  if(Rot / 10)
  // Display position 0 will show the first position of goal variable Rot
  matrix.writeDigitNum(0, (Rot / 10) );    
    // Display position 1 will show the second position of goal variable Rot      
    matrix.writeDigitNum(1, Rot % 10 );
    // A colon will be displayed between the two varialbes            
    matrix.drawColon(true);  
    
 // This if argument prevents from displaying a zero for other variable 
  if(Blau / 10)
    // Display position 3 will show the first position of goal variable Blau                     
    matrix.writeDigitNum(3, (Blau / 10) );   
    
    //  Display position 4 will show the second position of goal variable Blau     
    matrix.writeDigitNum(4, Blau % 10 );    
    // Display everyting above      
    matrix.writeDisplay();                       


   // 3 if-else arguments following for the two breakbeam sensors and the back to zero button 
   // If sensor light beam is broken, system reads status low and turns the control LED on                                     
  if (sensorState == LOW) {                 
    digitalWrite(LEDPIN, HIGH);             
  } 
  // otherwise no power for the control LED
  else {
    digitalWrite(LEDPIN, LOW);            
  }
  
  // If SensorState does not differ from lastState...
  // (The "!" reverses the signal state to function correclty.
  // Without it, the goal values constantly increase when light beams ar UNbroken)
  if (sensorState && !lastState) {                
                                                  
    // ...The message Unbroken would be displayed on Arduino's serial monitor                                              
    Serial.println("1 Unbroken");                 
                                               
  } 
  // If it differs, "Broken" would be displayed and the goal variable Red is increased. 
  if (!sensorState && lastState) {
    Serial.println("1 Broken");                                                               
    Rot = Rot + 1;                                 
  }
  
  // Same for other breakbeam sensor
  if (sensorState2 && !lastState2) {               
    Serial.println("2 Unbroken");
  }
  if (!sensorState2 && lastState2) {
    Serial.println("2 Broken");
    Blau = Blau + 1;                              
  }
  // Check status of back to zero button 
  if (sensorState3 && !lastState3) {               
  }
  // If pressed, the serial display would show "reset" and both goal variables are reset to zero.
  if (!sensorState3 && lastState3) {
    Serial.println("reset");                       
    Blau = 0;                                      
    Rot = 0;
    // Clears everything displayed on LED
    matrix.clear();
  }
 // Save the last sensor states 
  lastState = sensorState;                     
  lastState2 = sensorState2;                       
  lastState3 = sensorState3;
}                                                  
// End of programm. Restart void loop