Compilare: user.cpp: In function ‘int main()’: user.cpp:4:30: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("joc3.in","r",stdin); ^ user.cpp:5:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("joc3.out","w",stdout); ^ user.cpp:7:16: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&N); ^ user.cpp:8:37: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(i=1;i<=N;++i) scanf("%d",&a[i]); ^ user.cpp:15:31: warning: ‘P’ may be used uninitialized in this function [-Wmaybe-uninitialized] printf("%d %d\n",P,a[P]-(a[P]^s)); ^