Compilare: user.cpp: In function ‘int main()’: user.cpp:68:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("spider.in","r",stdin); ^ user.cpp:69:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("spider.out","w",stdout); ^ user.cpp:71:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&m,&n); ^ user.cpp:74:35: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&mat[i][j]); ^ user.cpp:87:19: warning: ‘vy’ may be used uninitialized in this function [-Wmaybe-uninitialized] while(sol[i][j]!=max){ ^ user.cpp:87:19: warning: ‘vx’ may be used uninitialized in this function [-Wmaybe-uninitialized]