Compilare: main.cpp: In function 'void build(int, int, int)': main.cpp:75:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(ind1<tree[2*nod].size() and ind2<tree[2*nod+1].size()) ~~~~^~~~~~~~~~~~~~~~~~~ main.cpp:75:43: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(ind1<tree[2*nod].size() and ind2<tree[2*nod+1].size()) ~~~~^~~~~~~~~~~~~~~~~~~~~ main.cpp:81:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(ind1<tree[2*nod].size()) ~~~~^~~~~~~~~~~~~~~~~~~ main.cpp:83:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(ind2<tree[2*nod+1].size()) ~~~~^~~~~~~~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:132:14: warning: unused variable 'che' [-Wunused-variable] char che=in.read_ch(); ^~~ main.cpp: In member function 'char InParser::read_ch()': main.cpp:13:29: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(buff, 1, 4096, fin); ^