foo.c: In function 'main':
foo.c:5:11: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'int' [-Wformat=]
  printf("%s\n",s[20]);
          ~^    ~~~~~
          %d
foo.c:5:17: warning: array subscript is above array bounds [-Warray-bounds]
  printf("%s\n",s[20]);
                ~^~~~

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