Compilare: In file included from /usr/include/c++/5/cassert:43:0, from /usr/include/x86_64-linux-gnu/c++/5/32/bits/stdc++.h:33, from user.cpp:1: user.cpp: In function ‘int main()’: user.cpp:73:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] assert(b.size() == 2 * n && a.size() == 2 * n); ^ user.cpp:73:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] assert(b.size() == 2 * n && a.size() == 2 * n); ^