Compilare: user.cpp: In function ‘void run_rmq()’: user.cpp:54:13: warning: unused variable ‘prev_p2’ [-Wunused-variable] int prev_p2 = (1 << (i - 1)); ^ user.cpp: In function ‘void read_and_solve()’: user.cpp:116:17: warning: unused variable ‘y’ [-Wunused-variable] int x , y; ^ user.cpp:128:13: warning: unused variable ‘cost’ [-Wunused-variable] int cost , x , y; ^ user.cpp:112:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &n, &m); ^ user.cpp:117:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &x); ^ user.cpp:129:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &x, &y); ^ user.cpp: In function ‘int main()’: user.cpp:148:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("lca.in","r",stdin); ^ user.cpp:149:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("lca.out","w",stdout); ^