RBG LED with button Arduino example, cycles colors 10x per second while the button is pressed

rgb_example.ino

// https://learn.adafruit.com/adafruit-arduino-lesson-3-rgb-leds/breadboard-layout

// http://www.arduino.cc/en/Tutorial/Button

/*
Adafruit Arduino - Lesson 3. RGB LED
*/
 
int redPin = 11;
int greenPin = 10;
int bluePin = 9;
int buttonPin = 2;
//uncomment this line if using a Common Anode LED
//#define COMMON_ANODE
 
void setup()
{
  pinMode(redPin, OUTPUT);
  pinMode(greenPin, OUTPUT);
  pinMode(bluePin, OUTPUT);  
  pinMode(buttonPin, INPUT);   
  
//digitalWrite(buttonPin, HIGH);       // turn on pullup resistors
}

int state = 0;

void loop()
{
  if(digitalRead(buttonPin)==1)
    state++;
  
  switch(state%6)
  {
    case 0:
  setColor(255, 0, 0);  // red
break;
    case 1:
  setColor(0, 255, 0);  // green
  break;
  case 2:
  setColor(0, 0, 255);  // blue
  break;
  case 3:
  setColor(255, 255, 0);  // yellow
  break;
  case 4:
  setColor(80, 0, 80);  // purple
  break;
  case 5:
  setColor(0, 255, 255);  // aqua
break;
default:

break;
  }
  delay(100);
}
 
void setColor(int red, int green, int blue)
{
  #ifdef COMMON_ANODE
    red = 255 - red;
    green = 255 - green;
    blue = 255 - blue;
  #endif
  int divisor = 12;
  analogWrite(redPin, red/divisor);
  analogWrite(greenPin, green/divisor);
  analogWrite(bluePin, blue/divisor);  
}