Compilare: user.cpp: In function ‘int BS(int, int)’: user.cpp:14:7: warning: statement has no effect [-Wunused-value] dr+n; ^ user.cpp:12:9: warning: variable ‘st’ set but not used [-Wunused-but-set-variable] int st, dr, val, s; ^ user.cpp:12:17: warning: unused variable ‘val’ [-Wunused-variable] int st, dr, val, s; ^ user.cpp: In function ‘int main()’: user.cpp:31:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<v.size()-2;i++) ^ user.cpp:33:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=i+1;j<v.size()-1;j++) ^ user.cpp:21:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("nrtri.in", "r", stdin); ^ user.cpp:22:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("nrtri.out", "w", stdout); ^ user.cpp:24:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d" ,&n); ^ user.cpp:27:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &x); ^