long time1 = 0; //this declares time1 as a long
                //and initialises it to 0;
long time2 = 0;
bool redPressed = false;
bool greenPressed = false;
int distanceCM = 400;
void setup() {
  Serial.begin(115200);
  pinMode(6, INPUT);   //THE GREEN BUTTON
  pinMode(5, INPUT);   //THE RED BUTTON
}
void loop() {
  if(digitalRead(5) == HIGH && redPressed == false){
    while(digitalRead(5) == HIGH){
      delay(1);
    }
    time1 = micros();
    Serial.print("Recorded Point A: ");
    Serial.println(time1);
    redPressed = true;
    greenPressed = false;
  }
  if(digitalRead(6) == HIGH && redPressed == true && greenPressed ==false){
    while(digitalRead(6) == HIGH){
        delay(1);
    }
    time2 = micros();
    long timeDiffernce = time2 - time1;
    Serial.println("Assuming a seperation of 100m");
    Serial.print("Time Differnce between A&B is ");
    Serial.println(timeDiffernce);
    greenPressed = true;
    redPressed = false;
    float speed = (distanceCM/100.0) / (timeDiffernce/1000000.0);
    Serial.print("Speed is: ");
    Serial.print(speed);
    Serial.println(" meters per second");
  }
}