Compilare: main.cpp: In function 'int32_t main()': main.cpp:171:28: warning: array subscript has type 'char' [-Wchar-subscripts] parent[total] = last[s[0]]; ^ main.cpp:172:29: warning: array subscript has type 'char' [-Wchar-subscripts] len[total] = len[last[s[0]]] + 1; ^ main.cpp:173:23: warning: array subscript has type 'char' [-Wchar-subscripts] if(len[last[s.back()]] < len[total]) ^ main.cpp:174:17: warning: array subscript has type 'char' [-Wchar-subscripts] last[s.back()] = total; ^ In file included from /usr/include/c++/6/ext/pb_ds/detail/pat_trie_/pat_trie_.hpp:45:0, from /usr/include/c++/6/ext/pb_ds/detail/container_base_dispatch.hpp:90, from /usr/include/c++/6/ext/pb_ds/assoc_container.hpp:48, from main.cpp:3: main.cpp:189:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] assert(sol == SOL.size()); ~~~~^~~~~~~~~~~~~ main.cpp:161:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen(PROB_NAME".in", "r", stdin); ^ main.cpp:163:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen(PROB_NAME".out", "w", stdout); ^