Compilare: user.cpp: In function ‘int Quick(int, int, int)’: user.cpp:20:54: warning: operation on ‘v[j]’ may be undefined [-Wsequence-point] if (i<=j) v[i]=v[i]^v[j]^(v[j]=v[i]),i++,j--; ^ user.cpp: In function ‘int main()’: user.cpp:28:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("sdo.in","r",stdin); ^ user.cpp:29:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("sdo.out","w",stdout); ^ user.cpp:30:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&n,&k); ^ user.cpp:32:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&v[i]); ^