Silly random 4 segment display thing for Arduino

4seg.cpp

#include <Arduino.h> 
#include <TM1637Display.h> 
#define CLK 2 
#define DIO 3 
TM1637Display display(CLK, DIO); 

void setup() 
{ 
  display.setBrightness(100); 
} 
void loop() 
{ 
  int i;
  uint8_t data[] = {0,0,0,0}; 
  display.setSegments(data); 
  while(1) {
    for(i=0; i<4; i++) {
      data[i] ^= (1 << random(7));
    }
    display.setSegments(data);
    delay(50); 
  }
}