Compilare: main.cpp: In constructor 'matrix::matrix(int, int)': main.cpp:17:9: warning: statement has no effect [-Wunused-value] n; ^ main.cpp: In member function 'matrix& matrix::operator=(matrix&)': main.cpp:59:9: warning: this 'for' clause does not guard... [-Wmisleading-indentation] for(int i=0; i<n; i++) ^~~ main.cpp:62:13: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for' n=y.n; ^