boxes.cpp: In function 'long long int delivery(int, int, int, int*)':
boxes.cpp:21:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
21 | for (int i = 0; i < a.size(); ++i)
| ~~^~~~~~~~~~
boxes.cpp:35:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
35 | for (int i = 0; i < b.size(); ++i)
| ~~^~~~~~~~~~
boxes.cpp:47:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
47 | for (int i = 0; i < a.size(); ++i)
| ~~^~~~~~~~~~
boxes.cpp:49:35: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
49 | res=min(res,l[i]+(a.size()>=i+2 ? r[a.size()-i-2] : 0));
| ~~~~~~~~^~~~~
boxes.cpp:50:37: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
50 | res=min(res,l[i]+L+(a.size()>i+k ? a[a.size()-k-i-1] : 1ll*0));
| ~~~~~~~~^~~~