/in/ex1.c: In function 'main':
/in/ex1.c:9:13: error: conversion to 'char' from 'int' may alter its value [-Werror=conversion]
         c = getchar();
             ^~~~~~~
/in/ex1.c:17:17: error: 'x' undeclared (first use in this function)
     printf("%d",x);
                 ^
/in/ex1.c:17:17: note: each undeclared identifier is reported only once for each function it appears in
/in/ex1.c:5:10: error: variable 'files' set but not used [-Werror=unused-but-set-variable]
     char files[10001];
          ^~~~~
cc1: all warnings being treated as errors