Compilare: user.cpp: In function ‘int find(long long int, long long int)’: user.cpp:51:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(it->fi.fi==xa&&it->fi.se==xb) ^ user.cpp:51:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(it->fi.fi==xa&&it->fi.se==xb) ^ user.cpp: In function ‘int main()’: user.cpp:199:33: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(s[i][j]<=10&&!viz[s[i][j]]) ^