Compilare: user.cpp: In function ‘int solve(int)’: user.cpp:26:36: warning: array subscript has type ‘char’ [-Wchar-subscripts] for (auto x : nextCharIndices[last]) { ^ user.cpp: In function ‘int main()’: user.cpp:51:31: warning: format ‘%s’ expects argument of type ‘char*’, but argument 2 has type ‘char (*)[20]’ [-Wformat=] code = scanf("%s", &words[n]); ^ user.cpp:45:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("text3.in", "r", stdin); ^ user.cpp:46:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("text3.out", "w", stdout); ^