#include <stdio.h>//For stdout  
#include"xplatform.h"//For cross-platform Xsleep()and xCls() 
void goToState(void);//Prototype /1 Define states (enumerated types-like ints) 
enum states {RED,REDAMBER,GREEN,AMBER}; 
int CurrState=-1; 
int main(void) {
  while(1) {
    xcls(); 
    printf("\nTraffic lights FSM\n"); 
    printf("Terminate with Ctr1- nln"); 
    goToState(); 
  }
return 0; 
}
void  goToState(void){
  currState++; 
  switch(currState){
    case RED: //Red light 
            printf("{R}In");
            printf("A \n");
            printf("G\n");
            break; 
    case REDAMBER: //Red + Amber lights 
printf("{R}\n"); 
printf("{A}\n"); 
printf("G\n");
 break; 
case GREEN: //Green light 
printf("R\n");
printf("A\n"); 
printf("{G}\n"); 
break; 
case AMBER: // Amber light 
printf("R\n"); 
printf("{A}\n"); 
printf("G\n"); 
CurrState =-1; //Continue ad naseum.... 
break; 
  }
xsleep(4000);//Timer delay;4 seconds
}