Compilare: user.cpp: In function ‘bool check(char, int)’: user.cpp:5:13: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(H[val].size()==0) ^ user.cpp:7:20: warning: array subscript has type ‘char’ [-Wchar-subscripts] for(j=0;j<H[val].size();j++){ ^ user.cpp:7:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<H[val].size();j++){ ^ user.cpp:8:15: warning: array subscript has type ‘char’ [-Wchar-subscripts] x=H[val][j]; ^ user.cpp:10:21: warning: array subscript has type ‘char’ [-Wchar-subscripts] while(i<H[val].size()&&H[val][i]+x!=pos) ^ user.cpp:10:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i<H[val].size()&&H[val][i]+x!=pos) ^ user.cpp:10:36: warning: array subscript has type ‘char’ [-Wchar-subscripts] while(i<H[val].size()&&H[val][i]+x!=pos) ^ user.cpp:12:19: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(i==H[val].size()) ^ user.cpp:12:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(i==H[val].size()) ^