File content as of revision 0:4e264e403d13:

#include "mbed.h"

    /*  Pin declaration for LED */
DigitalOut led1(LED1);
DigitalOut led2(LED2);
DigitalOut led3(dp27);
DigitalOut led4(dp26);

#define ACTIVELOW       // Comment out if the LED driver input is Active High
#define CYCLE 0.5       // Duration of turning on for each LED in second
#define NUMLED 4        // How many LEDs do you have? 


/* Dont change the lines below here */

#ifdef ACTIVELOW
#define LEDON 0
#define LEDOFF 1
#else
#define LEDON 1
#define LEDOFF 0
#endif /* ACTIVELOW */


int main() {
    
        /* repeat forever */
    while(1) {
            /* Turn on and off LED 1 */
        led1 = LEDON;
        wait(CYCLE);
        led1 = LEDOFF;
        
            /* Turn on and off LED 2 */
        led2 = LEDON;
        wait(CYCLE);
        led2 = LEDOFF;
        
            /* if only two LED, skip LED 3 and 4 */
#if NUMLED <= 2
        continue;
#endif
            /* Turn on and off LED 3 */
        led3 = LEDON;
        wait(CYCLE);
        led3 = LEDOFF;
        
            /* if only three LED, skip LED 4 */
#if NUMLED <= 3
        continue;
#endif
            /* Turn on and off LED 4 */
        led4 = LEDON;
        wait(CYCLE);
        led4 = LEDOFF;
    }}