Compilare: user.cpp: In function ‘int main()’: user.cpp:12:9: warning: array subscript has type ‘char’ [-Wchar-subscripts] fr[c]++; ^ user.cpp:20:17: warning: array subscript has type ‘char’ [-Wchar-subscripts] fr[c]++; ^ user.cpp:21:20: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(fr[c]>mx) ^ user.cpp:22:24: warning: array subscript has type ‘char’ [-Wchar-subscripts] mx=fr[c],d=c; ^ user.cpp:23:20: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(fr[c]<mn) ^ user.cpp:24:24: warning: array subscript has type ‘char’ [-Wchar-subscripts] mn=fr[c],e=c; ^ user.cpp:26:24: warning: array subscript has type ‘char’ [-Wchar-subscripts] mn=fr[c]; ^ user.cpp:30:21: warning: array subscript has type ‘char’ [-Wchar-subscripts] fr[e]--; ^ user.cpp:31:21: warning: array subscript has type ‘char’ [-Wchar-subscripts] fr[d]++; ^