Compilare: user.cpp: In member function ‘int PersistentSegmTree::update(int, int, int, int)’: user.cpp:63:21: warning: suggest parentheses around ‘+’ inside ‘>>’ [-Wparentheses] int mid = st+dr>>1; ~~^~~ In file included from /usr/include/c++/6/cassert:44:0, from /usr/include/x86_64-linux-gnu/c++/6/32/bits/stdc++.h:33, from user.cpp:1: user.cpp: In function ‘int Query(int, int, int, int, int)’: user.cpp:84:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] assert(left_nodes.size() == lines); ~~~~~~~~~~~~~~~~~~^~~~ user.cpp:85:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] assert(right_nodes.size() == lines); ~~~~~~~~~~~~~~~~~~~^~~~ user.cpp:100:20: warning: suggest parentheses around ‘+’ inside ‘>>’ [-Wparentheses] dr = st+dr>>1; ~~^~~ user.cpp:106:21: warning: suggest parentheses around ‘+’ inside ‘>>’ [-Wparentheses] st = (st+dr>>1)+1; ~~^~~