Eroare de compilare: user.cpp:12:11: error: ‘int clock’ redeclared as different kind of symbol int N, M, clock; ^ In file included from /usr/include/pthread.h:26:0, from /usr/local/include/c++/4.8.0/i686-pc-linux-gnu/bits/gthr-default.h:35, from /usr/local/include/c++/4.8.0/i686-pc-linux-gnu/bits/gthr.h:148, from /usr/local/include/c++/4.8.0/ext/atomicity.h:33, from /usr/local/include/c++/4.8.0/bits/ios_base.h:39, from /usr/local/include/c++/4.8.0/ios:42, from /usr/local/include/c++/4.8.0/ostream:38, from /usr/local/include/c++/4.8.0/iostream:39, from user.cpp:1: /usr/include/time.h:183:16: error: previous declaration of ‘clock_t clock()’ extern clock_t clock (void) __THROW; ^ user.cpp: In function ‘void DFS(int)’: user.cpp:17:17: error: ISO C++ forbids incrementing a pointer of type ‘clock_t (*)()throw () {aka long int (*)()throw ()}’ [-fpermissive] in[nod] = ++clock; ^ user.cpp:17:17: error: lvalue required as increment operand user.cpp:23:18: error: ISO C++ forbids incrementing a pointer of type ‘clock_t (*)()throw () {aka long int (*)()throw ()}’ [-fpermissive] out[nod] = ++clock; ^ user.cpp:23:18: error: lvalue required as increment operand