Compilare: main.cpp: In function 'void bkt(int, int (*)[21])': main.cpp:18:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 18 | for (int i = 0; i < ans.size(); ++i) { | ~~^~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:123:21: warning: unused variable 'x' [-Wunused-variable] 123 | for (int i = 1, x, y; i <= k; ++i) { | ^ main.cpp:123:24: warning: unused variable 'y' [-Wunused-variable] 123 | for (int i = 1, x, y; i <= k; ++i) { | ^