/in/foo.c: In function 'FindMax':
/in/foo.c:10:9: warning: 'maxi' may be used uninitialized in this function [-Wmaybe-uninitialized]
  return maxi;
         ^~~~
/in/foo.c: In function 'main':
/in/foo.c:22:2: warning: 'maxi' may be used uninitialized in this function [-Wmaybe-uninitialized]
  printf("%d",FindMax(a,n));
  ^~~~~~~~~~~~~~~~~~~~~~~~~