/**
 * Iteration over digital inputs. 
 * 
 * Iteration with a "for" structure over input pins.
 * button switches are wired from pins 0 to 3
 * depending the number of pressed buttons a variable
 * named "force" will hold different values from 0 to 4
 */

int force;
 
void setup() {
  Serial.begin(9600);
  for(int i = 0; i<4; i++) {  // sets pins 0-3 as inputs
    pinMode(i, INPUT);
  }
}

void loop() {
  force = 0;
  for(int i = 0; i<4; i++) {  // calculates how many buttons are pressed
    if(digitalRead(i) == HIGH) {
      force = force + 1;  // add 1 to force if the button is pressed
    }
  }
  Serial.print("force is: ");  // print the force value
  Serial.println(force);
  delay(200);  // wait 200ms for next reading
}

