Compilare: In file included from /usr/include/c++/4.8/cassert:43:0, from /usr/include/i386-linux-gnu/c++/4.8/bits/stdc++.h:33, from user.cpp:1: user.cpp: In member function ‘void HeavyLight::Preprocess()’: user.cpp:23:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] assert(dfs_sub(0, -1) == T.size()); ^ user.cpp: In function ‘int main()’: user.cpp:112:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("heavypath.in", "r", stdin); ^ user.cpp:113:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("heavypath.out", "w", stdout); ^