foo.cc:3:11: error: '::main' must return 'int'
 void main()
           ^
foo.cc: In function 'int main()':
foo.cc:6:8: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
  gets(x);
        ^
In file included from /usr/include/stdio.h:862:0,
                 from foo.cc:1:
/usr/include/x86_64-linux-gnu/bits/stdio2.h:232:1: note: declared here
 gets (char *__str)
 ^~~~
foo.cc:7:16: error: 'strrev' was not declared in this scope
  printf("%s\n",strrev(x));
                ^~~~~~
foo.cc:7:16: note: suggested alternative: 'strsep'
  printf("%s\n",strrev(x));
                ^~~~~~
                strsep
foo.cc:6:6: warning: ignoring return value of 'char* gets(char*)', declared with attribute warn_unused_result [-Wunused-result]
  gets(x);
  ~~~~^~~

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