Compilare: user.cpp: In function ‘void build(int, int, int)’: user.cpp:27:48: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int i = 0, j = 0; i < A[Nst].size() || j < A[Ndr].size(); ){ ^ user.cpp:27:69: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int i = 0, j = 0; i < A[Nst].size() || j < A[Ndr].size(); ){ ^ user.cpp:28:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if( i == A[Nst].size() ){ ^ user.cpp:32:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if( j == A[Ndr].size() ){ ^