I'm thinking your sketch needs to look more like this. I moved the bit that outputs into the loop. You had it outside with index set to a value that was out of range for your array.
char *switchPinNames[] = {
"Red switch", "Green switch", "Yellow switch"};
char *ledPinNames[] = {
"Red", "Green", "Yellow"};
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 LEDsvoid setup()
{
Serial.begin(9600);
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++)
{if(digitalRead(inputPins[index]) == HIGH)
{
digitalWrite(ledPins[index], HIGH);
Serial.print(switchPinNames[index]);
Serial.print(" is pressed, so the ");
Serial.print(ledPinNames[index]);
Serial.println(" LED was turned on");
}else
{
digitalWrite(ledPins[index], LOW); // turn LED off
}
}
}
The value of index is what points to the desired element in your array.