int rled = 23;
int bled = 21;
int gled = 22;
int sensorValue = 0;
int flexDegree = 0;
int sensorPin = 35;
void setup()
{
  pinMode(sensorPin, INPUT);
  Serial.begin(115200);
  pinMode(rled,OUTPUT);
  pinMode(bled,OUTPUT);
  pinMode(gled,OUTPUT);
}

void loop()
{
  // read the sensor value:
  sensorValue = analogRead(sensorPin);
  flexDegree = map(sensorValue,159,511,0,180);
  //print out the value you read:
  Serial.println(flexDegree);
  if(flexDegree >= 50){
    digitalWrite(rled, HIGH);
    digitalWrite(gled, LOW);
    digitalWrite(bled, LOW);
    delay(100);
  }
  else if (flexDegree >= 20){
    digitalWrite(bled, HIGH);
    digitalWrite(rled, LOW);
    digitalWrite(gled, LOW);
    delay(100);
  }
  else{
    digitalWrite(gled, HIGH);
    digitalWrite(rled, LOW);
    digitalWrite(bled, LOW);
    delay(100);
  }
 }