Mine

#include "stdio.h"
#include "stdlib.h"
 
#define RTHRESH_BLACK 50
#define LTHRESH_BLACK 50
#define RTHRESH_GREY 40
#define LTHRESH_GREY 40
 
int LSENSOR=1;
int RSENSOR=2;
int retval=0;
int nothing;
 
void untilfunction(int obst)
{
 switch (obst)
 {
  /* The first selection */
  /* turn left opun black line */
  case 1:
   if (LSENSOR<=LTHRESH_BLACK || RSENSOR<=RTHRESH_BLACK)
   { retval=1; }
   else
   { retval=0; }
   break;
 
  /* pre-gate selection */
  /* returns true wgeb both sensors hit grey */
  case 2:
   printf ("if %d<=%d",LSENSOR,LTHRESH_GREY);
   if (LSENSOR<=LTHRESH_GREY && RSENSOR<=RTHRESH_GREY)
   { retval=1; }
   else
   { retval=0; }
   break;
 
 
 }
}
 
 
void initsensors()
{
/*
 SetSensor(SENSOR_1,SENSOR_LIGHT);
 SetSensor(SENSOR_2,SENSOR_TOUCH);
 SetSensor(SENSOR_3,SENSOR_LIGHT);
 SetSensorMode(SENSOR_1, SENSOR_MODE_PERCENT);
 SelectDisplay(DISPLAY_SENSOR_1);
 */
}
 
void turnleft()
{
 /*
 OnFwd(LMOTOR);
 OnRev(RMOTOR);
 Wait(200);
 Off(OUT_A+OUT_C);
 */
}
 
void leftpath() {
 printf("PATH: %s SENSOR: %d\n", "LEFT  ", LSENSOR );
}
void rightpath() {
 printf("PATH: %s SENSOR: %d\n", "RIGHT ", LSENSOR);
}
 
void followline(int untilobst)
{
 while (1)
 {
 untilfunction(untilobst);
 if (retval==1) { printf("return\x0a"); return; }
  {
   if (LSENSOR<=LTHRESH_BLACK)
   {
    rightpath();
   }
   else if (RSENSOR<=RTHRESH_BLACK)
   {
    printf("%s", "HELLO");
    leftpath();
   }
   else { printf("CURRENT PATH: %s SENSOR: %d\x0a", "PREVIOUS ",LSENSOR); }
   if (LSENSOR==49) { RSENSOR=51; }
   LSENSOR-=1;
   RSENSOR-=1;
  }
 }
 printf("grey sensors hit\x0a");
 
}
 
int main()
{
 LSENSOR=60;
 RSENSOR=60;
 followline(2);
}