Compilare: user.cpp: In function ‘void tsort(int, int, int)’: user.cpp:21:27: warning: array subscript has type ‘char’ [-Wchar-subscripts] char mid = (w[s[lo][pos]] + w[s[hi][pos]]) / 2; ^ user.cpp:21:43: warning: array subscript has type ‘char’ [-Wchar-subscripts] char mid = (w[s[lo][pos]] + w[s[hi][pos]]) / 2; ^ user.cpp:26:12: warning: array subscript has type ‘char’ [-Wchar-subscripts] if (w[c] < mid) { ^ user.cpp:32:19: warning: array subscript has type ‘char’ [-Wchar-subscripts] } else if (w[c] > mid) { ^ user.cpp: In function ‘int main()’: user.cpp:53:34: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d%d ", &choice, &n); ^ user.cpp:58:27: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, " %s", s[i]); ^