Eroare de compilare: user.cpp: In function ‘int solve(int)’: user.cpp:21:38: error: ‘strlen’ was not declared in this scope char last = words[i][strlen(words[i]) - 1] - 'a'; ^ user.cpp:26:18: warning: array subscript has type ‘char’ [-Wchar-subscripts] if (exists[last][j]) { ^ user.cpp: In function ‘int main()’: user.cpp:49:31: warning: format ‘%s’ expects argument of type ‘char*’, but argument 2 has type ‘char (*)[20]’ [-Wformat=] code = scanf("%s", &words[n]); ^ user.cpp:43:33: 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:44:35: 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); ^