Compilare: user.cpp: In function ‘void refresh(int)’: user.cpp:33:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i<aint[2*nod].v.size()&&j<aint[2*nod+1].v.size()){ ^ user.cpp:33:58: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i<aint[2*nod].v.size()&&j<aint[2*nod+1].v.size()){ ^ user.cpp:43:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i<aint[2*nod].v.size()){ ^ user.cpp:47:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(j<aint[2*nod+1].v.size()){ ^ user.cpp: In function ‘std::vector<int> inter(std::vector<int>, std::vector<int>)’: user.cpp:83:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i<a.size()&&j<b.size()){ ^ user.cpp:83:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i<a.size()&&j<b.size()){ ^ user.cpp:93:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i<a.size()){ ^ user.cpp:97:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(j<b.size()){ ^ user.cpp: In function ‘char nextch()’: user.cpp:9:29: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buf,1,MAXBUF,fi); ^