Compilare: user.cpp: In function ‘void df(int)’: user.cpp:50:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(up != nodes.size() - 1) { ^ user.cpp:52:53: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while((1 << (j + 1)) <= nodes.size() - up - 1) ^ user.cpp:60:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i = 0; i < con[nod].size(); i++) { ^ user.cpp: In function ‘int main()’: user.cpp:75:12: warning: unused variable ‘j’ [-Wunused-variable] int i, j; ^ user.cpp:76:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("spiridusi.in", "r", stdin); ^ user.cpp:77:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("spiridusi.out", "w", stdout); ^ user.cpp:78:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &N, &C); ^ user.cpp:80:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &s[i]); ^ user.cpp:82:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &p[i]); ^ user.cpp:84:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &x, &y); ^