foo.cc:4:24: error: 'int time' redeclared as different kind of symbol
 int b[10100],c[101001],time,z[4]={0,0,0,0};
                        ^~~~
In file included from /usr/include/pthread.h:24:0,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/gthr-default.h:35,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/gthr.h:148,
                 from /usr/include/c++/7/ext/atomicity.h:35,
                 from /usr/include/c++/7/bits/ios_base.h:39,
                 from /usr/include/c++/7/ios:42,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from foo.cc:1:
/usr/include/time.h:75:15: note: previous declaration 'time_t time(time_t*)'
 extern time_t time (time_t *__timer) __THROW;
               ^~~~
foo.cc: In function 'void nm(int, int)':
foo.cc:15:8: error: expected primary-expression before ']' token
   if(a[][])
        ^
foo.cc:15:10: error: expected primary-expression before ']' token
   if(a[][])
          ^
foo.cc:16:2: error: expected primary-expression before '}' token
  }
  ^

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