exercise 4

float sensorValue = 0; // variable for sensor value
float sensorPin = A0; // variable for sensor pin
int greenLedPin = 10;
int yellowLedPin = 9;

void setup() {
 pinMode(sensorPin, INPUT);
 Serial.begin(9600);
 pinMode(greenLedPin, OUTPUT);
 pinMode(yellowLedPin, OUTPUT);
}
void loop() {
 sensorValue = analogRead(sensorPin);
 sensorValue = ((125-sensorValue) /450)*255;
 Serial.println(sensorValue); // print out sensorValue to the Serial Monitor
 delay(20); // delay for 0.2 seconds
  analogWrite(greenLedPin, sensorValue);
 analogWrite(yellowLedPin, sensorValue);
}