#include <FastLED.h>

// How many leds in your strip?
#define NUM_LEDS 10

// For led chips like Neopixels, which have a data line, ground, and power, you just
// need to define DATA_PIN.  For led chipsets that are SPI based (four wires - data, clock,
// ground, and power), like the LPD8806 define both DATA_PIN and CLOCK_PIN
#define DATA_PIN 3
#define CLOCK_PIN 13

// Define the array of leds
CRGB leds[NUM_LEDS];

void setup() {
  FastLED.addLeds<NEOPIXEL, DATA_PIN>(leds, NUM_LEDS);
}

void loop()
{
  // set the colours
  for (int cnt = 0; cnt < 5; cnt++)
  {
    leds[cnt] = CRGB::Red;
  }
  for (int cnt = 5; cnt < 10; cnt++)
  {
    leds[cnt] = CRGB::Blue;
  }
  // and show
  FastLED.show();
  delay(500);

  // clear the strip
  for (int cnt = 0; cnt < 10; cnt++)
  {
    leds[cnt] = CRGB::Black;
  }
  FastLED.show();
  delay(500);
}