help with loop!!!!!! plz

[poreko]

I am trying to write a Traffic-Light control program using C which will ask the user to chose an initial state,then the program program has to continue with the correct state for both lights, which follows the initial state indicated by the user.
eg: if I chose initial state=4 the program has to go trought 4,5,6,1,2,and then stop at 3.

this is the code i have written so far:
------------------------------------------------------------------------------------
#include<stdio.h>

void main(void)

{

int state;
int counter;
int state2;


printf("Please give a value to start\n");
scanf("%d",&state2);
fflush(stdin);


printf("LIGHTS 1 LIGHTS 2 \n");

while(state<=6)
{



for(state=state2;state<=6;state++)
{




switch(state)
{
case 1:

printf(" 1 RED GREEN \n");
break;

case 2:

printf(" 2 RED AMBER \n");
break;

case 3:

printf(" 3 RED+AMBER RED \n");
break;

case 4:
printf(" 4 GREEN RED \n" );
break;

case 5:
printf(" 5 AMBER RED \n");
break;

case 6:
printf(" 6 RED RED+ AMBER \n ");
break;

default:

printf("You have entered a wrong number\n");
break;




} getchar();


}
if(state>6)







{

state2= state-6;


}


}


}

[DeMan]

You could use a while loop instead of a for loop, because you always want your state to loop (and always be <=6, which could make the for loop loop forever).

A simpler alternative (which should work) is to change your switch statement to

switch(state%6) //This gives the remainder when divided by 6, so 7 ==1 (mod 6) as req'd
{
  case 1:
    printf(" 1 RED GREEN \n");
  break;
 
  case 2:
    printf(" 2 RED AMBER \n");
  break;
 
  case 3: 
    printf(" 3 RED+AMBER RED \n");
  break;
 
  case 4:
    printf(" 4 GREEN RED \n" );
  break;
 
  case 5:
    printf(" 5 AMBER RED \n");
  break;
 
  case 0:  //This now has to be 0 since 6 % 6 ==0, you may need to move this up the top, 
            //although I think case statements can be in any order
    printf(" 6 RED RED+ AMBER \n ");
  break;
 
  default:
    printf("It should now be impossible to get here even with ridiculous input");
  break;
}