Compilare: main.cpp: In function 'bool var()': main.cpp:41:23: warning: array subscript has type 'char' [-Wchar-subscripts] r = v[x[i]]; ^ main.cpp: In function 'int main()': main.cpp:78:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i<strlen(buff);i++) ~^~~~~~~~~~~~~ main.cpp:125:15: warning: array subscript has type 'char' [-Wchar-subscripts] v[y[k]] = !v[y[k]]; ^ main.cpp:125:26: warning: array subscript has type 'char' [-Wchar-subscripts] v[y[k]] = !v[y[k]]; ^