foo.c: In function 'one':
foo.c:16:1: warning: control reaches end of non-void function [-Wreturn-type]
   16 | }
      | ^
foo.c: In function 'main':
foo.c:23:9: warning: 'cnt' is used uninitialized [-Wuninitialized]
   23 |         printf("%d\n",cnt);
      |         ^~~~~~~~~~~~~~~~~~
foo.c:20:15: note: 'cnt' was declared here
   20 |         int x,cnt;
      |               ^~~

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