Compilare: main.cpp: In function 'int main()': main.cpp:72:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 72 | for (int j = 0; j < prev.size(); j++) { | ~~^~~~~~~~~~~~~ main.cpp:26:7: warning: unused variable 'x' [-Wunused-variable] 26 | int x, y; | ^ main.cpp:26:10: warning: unused variable 'y' [-Wunused-variable] 26 | int x, y; | ^