Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:56:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < graph[node].size(); ++ i) { ^ user.cpp: In function ‘void compute_dp(int)’: user.cpp:134:57: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < paths_which_pass[node].size(); ++ i) ^ user.cpp:140:46: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < graph[node].size(); ++ i) ^ user.cpp:141:71: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < paths_which_pass[graph[node][i]].size(); ++ j) ^ user.cpp:149:62: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < paths_which_start[node].size(); ++ i) { ^ user.cpp:169:50: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < graph[node].size(); ++ i) { ^ user.cpp: In constructor ‘InputReader::InputReader(const char*)’: user.cpp:13:47: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buffer, SIZE, 1, input_file); ^ user.cpp: In member function ‘void InputReader::advance()’: user.cpp:35:51: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buffer, SIZE, 1, input_file); ^