Blink LED with function?

Projects General Guidance
1

When a switch is pressed, it should blink the appropriate LED. There is two LED functions for small and large particles passing through a photo resistor which is being bombarded with a laser.

The serial monitor should count the large and small particles.

2

How does a single photo resistor count large and small particles?

3

Using an external switch.

Here is the code i did already, its not correct.

#define A0 0
#define large 9
#define small 4
#define sw 12

void smallParticleBlinkLED()
{
  int swSmall = digitalRead(sw);
  int sensorValue = analogRead(A0);
  float smallParticleBlinkLED=sensorValue;
  Serial.println(smallParticleBlinkLED);
  while(swSmall == LOW)
  {
    if(smallParticleBlinkLED>=20.46)
    {
      digitalWrite(small, HIGH);
    }else
    {
      digitalWrite(small, LOW);
    }
} }
void largeParticleBlinkLED()
{
  
  int swLarge = digitalRead(sw);
  
  int sensorValue = analogRead(A0);
  float largeParticleBlinkLED=sensorValue;
  Serial.println(largeParticleBlinkLED);
  while(swLarge == LOW)
  {
  if(largeParticleBlinkLED>=81.84)
  {
    digitalWrite(large, HIGH);
  }else
  {
    digitalWrite(large, LOW);
  }
    
} }
void setup()
{
  //pinMode(9,OUTPUT);
  //pinMode(4, OUTPUT);
  //pinMode(12,INPUT_PULLUP);  
  
  
 DDRD = (1<<9 | 1<<4); //OUTPUT LED's
 DDRB = (1<<4);      //set INPUT switch
 PORTB |= (1<<4);   //pullup resistor
  Serial.begin(9600);   //begin serial monitor
}


void loop()
{{
  largeParticleBlinkLED();
  delay(1);
  smallParticleBlinkLED();
  delay(1);
}
}