Compilare: user.cpp: In function ‘int main()’: user.cpp:65:35: warning: array subscript has type ‘char’ [-Wchar-subscripts] int cost=a[str[pr]][d] + a[str[ult]][d]; ^ user.cpp:65:52: warning: array subscript has type ‘char’ [-Wchar-subscripts] int cost=a[str[pr]][d] + a[str[ult]][d]; ^ user.cpp:90:24: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(a[str[i]][j]!=INF) ^