Compilare: user.cpp: In function ‘int afis()’: user.cpp:24:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ user.cpp: In function ‘int back(long int, long int)’: user.cpp:55:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ user.cpp: In function ‘int main()’: user.cpp:58:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("immortal.in","r",stdin); ^ user.cpp:59:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("immortal.out","w",stdout); ^ user.cpp:60:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%ld%ld%ld",&n,&m,&k); ^ user.cpp:63:41: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%ld%ld",&x,&y),a[x][y]=1; ^