foo.c: In function 'main':
foo.c:6:9: warning: implicit declaration of function 'gests'; did you mean 'gets'? [-Wimplicit-function-declaration]
    6 |         gests(str);
      |         ^~~~~
      |         gets
foo.c:7:19: warning: initialization of 'int' from 'size_t (*)(const char *)' {aka 'long unsigned int (*)(const char *)'} makes integer from pointer without a cast [-Wint-conversion]
    7 |         int len = strlen,left = 0,right = len;
      |                   ^~~~~~
foo.c:19:18: error: expected ')' before '\U0000ff1f'
   19 |         puts(flag ？ “Yes” ： “No”）；
      |             ~    ^~~
      |                  )
foo.c:19:22: error: stray '\342' in program
   19 |         puts(flag <U+FF1F> <U+201C>Yes<U+201D> <U+FF1A> <U+201C>No<U+201D><U+FF09><U+FF1B>
      |                            ^~~~~~~~
foo.c:19:26: error: stray '\342' in program
   19 |         puts(flag <U+FF1F> <U+201C>Yes<U+201D> <U+FF1A> <U+201C>No<U+201D><U+FF09><U+FF1B>
      |                                       ^~~~~~~~
foo.c:19:31: error: stray '\342' in program
   19 |         puts(flag <U+FF1F> <U+201C>Yes<U+201D> <U+FF1A> <U+201C>No<U+201D><U+FF09><U+FF1B>
      |                                                         ^~~~~~~~
foo.c:19:34: error: stray '\342' in program
   19 |         puts(flag <U+FF1F> <U+201C>Yes<U+201D> <U+FF1A> <U+201C>No<U+201D><U+FF09><U+FF1B>
      |                                                                   ^~~~~~~~
foo.c:19:14: error: incompatible type for argument 1 of 'puts'
   19 |         puts(flag ？ “Yes” ： “No”）；
      |              ^~~~
      |              |
      |              _Bool
In file included from foo.c:1:
/nix/store/3w4yrspgcx1z9wi18rv0hbap4jjlhx4c-glibc-2.37-8-dev/include/stdio.h:661:30: note: expected 'const char *' but argument is of type '_Bool'
  661 | extern int puts (const char *__s);
      |                  ~~~~~~~~~~~~^~~
foo.c:19:39: error: expected ';' before '}' token
   19 |         puts(flag ？ “Yes” ： “No”）；
      |                                       ^
      |                                       ;
   20 | }
      | ~                                      

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