Compilare: user.cpp: In function ‘int main()’: user.cpp:20:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rj.in","r",stdin); ^ user.cpp:21:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rj.out","w",stdout); ^ user.cpp:24:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%hd%hd",&n,&m); ^ user.cpp:27:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("\n"); ^ user.cpp:30:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%c",&x); ^ user.cpp:75:13: warning: ‘y2’ may be used uninitialized in this function [-Wmaybe-uninitialized] j[x2][y2]=0; ^ user.cpp:75:13: warning: ‘x2’ may be used uninitialized in this function [-Wmaybe-uninitialized] user.cpp:56:13: warning: ‘y1’ may be used uninitialized in this function [-Wmaybe-uninitialized] r[x1][y1]=0; ^ user.cpp:56:13: warning: ‘x1’ may be used uninitialized in this function [-Wmaybe-uninitialized]