Compilare: main.cpp: In function 'int main()': main.cpp:18:25: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare] 18 | if(n-v[i].size()==i&&v[i].size()>Max&&v[i].size()>0){Max=v[i].size();j=i;} | ~~~~~~~~~~~~~^~~ main.cpp:18:41: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare] 18 | if(n-v[i].size()==i&&v[i].size()>Max&&v[i].size()>0){Max=v[i].size();j=i;} | ~~~~~~~~~~~^~~~ main.cpp:20:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 20 | for(i=0;i<v[j].size();i++) | ~^~~~~~~~~~~~ In file included from /usr/include/c++/12.2.1/vector:64, from main.cpp:2: In member function 'constexpr std::vector<_Tp, _Alloc>::size_type std::vector<_Tp, _Alloc>::size() const [with _Tp = int; _Alloc = std::allocator<int>]', inlined from 'int main()' at main.cpp:20:24: /usr/include/c++/12.2.1/bits/stl_vector.h:988:66: warning: 'j' may be used uninitialized [-Wmaybe-uninitialized] 988 | { return size_type(this->_M_impl._M_finish - this->_M_impl._M_start); } | ~~~~~~~~~~~~~~^~~~~~~~ main.cpp: In function 'int main()': main.cpp:9:19: note: 'j' was declared here 9 | int n,i,Max=0,j,x; | ^