Compilare: main.cpp: In function 'void sift_down()': main.cpp:25:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 25 | while (2 * i + 1 < heap.size()) { | ~~~~~~~~~~^~~~~~~~~~~~~ main.cpp:29:25: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 29 | if (right_child < heap.size() && heap[right_child] < heap[left_child]) { | ~~~~~~~~~~~~^~~~~~~~~~~~~ main.cpp:21:9: warning: unused variable 'x' [-Wunused-variable] 21 | int x = heap[0]; | ^ main.cpp: In function 'int main()': main.cpp:67:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 67 | if (index < heap.size()) { | ~~~~~~^~~~~~~~~~~~~