// code to designate the pins for both the coloums and rows which will later be declared
int colAnodes[] {25, 35, 45};
int rowCathodes[] {29, 39, 49};
// when timer hits designated milisecond time, 1000 2000 or 3000, the grid displays the L W or S time dependent on the count
unsigned long showLTime = millis() + 1000; 
unsigned long showWTime = millis() + 2000; 
unsigned long showSTime = millis() + 3000;

void setup() {
//turns the coloum pins low, declares the colum pins as output.
  for (int pointer = 0; pointer <= sizeof(colAnodes) / sizeof(colAnodes[0]); pointer ++) {
    pinMode(colAnodes[pointer], OUTPUT);
    digitalWrite(colAnodes[pointer], LOW);
  }
// turns the row pins high, and declares them as output. 
  for (int pointer = 0; pointer <= sizeof(rowCathodes) / sizeof(rowCathodes[0]); pointer ++) {
    pinMode(rowCathodes[pointer], OUTPUT);
    digitalWrite(rowCathodes[pointer], HIGH);
  }

}

void loop() {
   // turns on certain LEDs on the grid.

  if(millis() < showLTime){
    //used to display L.
    lightLED(0, 0);
    lightLED(1, 0);
    lightLED(2, 0);
    //lightLED(0, 1);
    lightLED(2, 1);
    //lightLED(2, 2);
    //lightLED(0, 2);
    //lightLED(1, 2);
    lightLED(2, 2);

  } 

  if ((millis()> showLTime) && (millis()<showWTime)){
   // displays W
    lightLED(0, 0);
    lightLED(1, 0);
    lightLED(2, 0);
    //lightLED(0, 1);
    lightLED(2, 1);
    lightLED(2, 2);
    lightLED(0, 2);
    lightLED(1, 2);
    lightLED(2, 2);
    lightLED (1,1);
  }

  if ((millis()> showWTime) && (millis()<showSTime)){
    //displays S
    lightLED(0, 0);
    lightLED(1, 0);
    lightLED(2, 0);
    lightLED(0, 1);
    lightLED(2, 1);
    lightLED(2, 2);
    lightLED(0, 2);
    lightLED(1, 2);
    lightLED(2, 2);
    lightLED(1, 1);
  }
  //restarts the timer so that the letters restart the printing process.
  if(millis() > showSTime){
    showLTime = millis() +1000;
    showWTime = millis() +2000;
    showSTime = millis() +3000;
  }
} 
  



void lightLED(int row, int col) {
//lightLED is set to void, and is used to turn on and off the power of the coloums and rows.

  for (int pointer = 0; pointer <= sizeof(colAnodes) / sizeof(colAnodes[0]); pointer ++) {
    digitalWrite(colAnodes[pointer], LOW);
  }

  for (int pointer = 0; pointer <= sizeof(rowCathodes) / sizeof(rowCathodes[0]); pointer ++) {
    digitalWrite(rowCathodes[pointer], HIGH);
  }
  
  digitalWrite(rowCathodes[row], LOW);
  digitalWrite(colAnodes[col], HIGH);
}