/in/foo.c: In function 'Find_Max_Index':
/in/foo.c:22:9: warning: 'index' may be used uninitialized in this function [-Wmaybe-uninitialized]
  return index;
         ^~~~~
/in/foo.c: In function 'main':
/in/foo.c:30:2: warning: 'index' may be used uninitialized in this function [-Wmaybe-uninitialized]
  printf("%d", index);
  ^~~~~~~~~~~~~~~~~~~