skyline.cpp: In function 'void calc(int, int, std::vector<int>, int)':
skyline.cpp:23:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
23 | while (!v[l] && l < v.size()) l++;
| ~~^~~~~~~~~~
skyline.cpp:25:8: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
25 | if (l == v.size()) {mn = min(mn, k); return ;}
| ~~^~~~~~~~~~~
skyline.cpp:28:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
28 | if (!v[i] || i == v.size()) break ;
| ~~^~~~~~~~~~~