Compilare: user.cpp: In member function ‘void Path::reversePathAndMakeTree()’: user.cpp:192:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(nn < P.size()) nn <<= 1; ~~~^~~~~~~~~~ user.cpp:195:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i <= P.size(); ++ i) { ~~^~~~~~~~~~~ user.cpp: In function ‘int solve1(int, int)’: user.cpp:247:5: warning: this ‘if’ clause does not guard... [-Wmisleading-indentation] if (nodes[paths[nodes[a].pat].par].niv < nodes[paths[nodes[b].pat].par].niv) ^~ user.cpp:250:9: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the ‘if’ ans = max(paths[nodes[a].pat].query(1, 1, paths[nodes[a].pat].P.size(), 1, nodes[a].pos), ans); ^~~ user.cpp: In member function ‘char InParser::read_ch()’: user.cpp:21:38: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buff, 1, 4096, fin); ^