Compilare: main.cpp: In member function 'void heap::downheap(int)': main.cpp:18:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (index >= data.size()) { ~~~~~~^~~~~~~~~~~~~~ main.cpp:25:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (left_child < data.size()) { ~~~~~~~~~~~^~~~~~~~~~~~~ main.cpp:28:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (right_child < data.size() && data[right_child] < data[left_child]) { ~~~~~~~~~~~~^~~~~~~~~~~~~ main.cpp: In member function 'void heap::print()': main.cpp:98:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < data.size(); i++) { ~~^~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:127:23: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%i", &n); ^ main.cpp:135:24: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%i", &x); ^ main.cpp:139:27: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%i", &num); ^ main.cpp:143:27: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%i", &num); ^