Compilare: user.cpp: In function ‘int main()’: user.cpp:46:8: warning: suggest parentheses around ‘+’ inside ‘>>’ [-Wparentheses] fin>>a+1>>b+1; ^ user.cpp:46:13: warning: suggest parentheses around ‘+’ inside ‘>>’ [-Wparentheses] fin>>a+1>>b+1; ^ user.cpp:58:12: warning: array subscript has type ‘char’ [-Wchar-subscripts] j=pref[n]; ^ user.cpp:64:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<v.size();++i) ^