int inputPins[] = {2,3,4,5}; // create an array of pins for switch inputs
int ledPins[] = {10,11,12,13}; // create array of output pins for LEDs
void setup()
{ for(int index =
0; index <
4; index++)
{
pinMode(ledPins[index], OUTPUT); // declare LED as output
pinMode(inputPins[index], INPUT); // declare pushbutton as input
digitalWrite(inputPins[index],HIGH); // enable pull-up resistors
//(see Recipe 5.2)
}}
void loop(){
for(int index = 0; index < 4; index++)
{int val = digitalRead(inputPins[index]); // read input value
if (val == LOW) // check if the switch is pressed
{
digitalWrite(ledPins[index], HIGH); // turn LED on if switch is pressed
}
else
{
digitalWrite(ledPins[index], LOW); // turn LED off 
  }
 }
}