Compilare: main.cpp: In function 'int main()': main.cpp:69:29: warning: array subscript has type 'char' [-Wchar-subscripts] 69 | last[i][0] = fr[a[i]]; | ^ main.cpp:70:16: warning: array subscript has type 'char' [-Wchar-subscripts] 70 | fr[a[i]] = i; | ^ main.cpp:76:29: warning: array subscript has type 'char' [-Wchar-subscripts] 76 | last[i][1] = fr[b[i]]; | ^ main.cpp:77:16: warning: array subscript has type 'char' [-Wchar-subscripts] 77 | fr[b[i]] = i; | ^