Eroare de compilare: user.cpp:13:5: error: ‘int y0’ redeclared as different kind of symbol int y0=1; ^ In file included from /usr/include/features.h:357:0, from /usr/include/i386-linux-gnu/c++/4.8/bits/os_defines.h:39, from /usr/include/i386-linux-gnu/c++/4.8/bits/c++config.h:420, from /usr/include/c++/4.8/iosfwd:38, from /usr/include/c++/4.8/ios:38, from /usr/include/c++/4.8/istream:38, from /usr/include/c++/4.8/fstream:38, from user.cpp:1: /usr/include/i386-linux-gnu/bits/mathcalls.h:242:1: error: previous declaration of ‘double y0(double)’ __MATHCALL (y0,, (_Mdouble_)); ^ user.cpp: In function ‘void read()’: user.cpp:56:19: error: ISO C++ forbids decrementing a pointer of type ‘double (*)(double)throw ()’ [-fpermissive] --y0; ^ user.cpp:56:19: error: lvalue required as decrement operand user.cpp: In function ‘void matrix()’: user.cpp:98:21: warning: pointer to a function used in arithmetic [-Wpointer-arith] a[i+y0][j+x0] = 1; ^ user.cpp:98:23: error: invalid types ‘bool [210][210][double (*)(double)throw ()]’ for array subscript a[i+y0][j+x0] = 1; ^ user.cpp: In function ‘void surround()’: user.cpp:102:17: warning: pointer to a function used in arithmetic [-Wpointer-arith] nl = y0 + 2*n - 1; ^ user.cpp:102:21: warning: pointer to a function used in arithmetic [-Wpointer-arith] nl = y0 + 2*n - 1; ^ user.cpp:102:19: error: invalid conversion from ‘double (*)(double)throw ()’ to ‘int’ [-fpermissive] nl = y0 + 2*n - 1; ^