Compilare: main.cpp: In function 'int factor()': main.cpp:43:23: warning: array subscript has type 'char' [-Wchar-subscripts] r=val[v[i]]; ^ main.cpp:54:23: warning: array subscript has type 'char' [-Wchar-subscripts] r=val[v[i]]; ^ main.cpp: In function 'int main()': main.cpp:65:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<strlen(s);i++){ ~^~~~~~~~~~ main.cpp:105:14: warning: array subscript has type 'char' [-Wchar-subscripts] val[c]=1-val[c]; ^ main.cpp:105:23: warning: array subscript has type 'char' [-Wchar-subscripts] val[c]=1-val[c]; ^