Compilare: user.cpp: In function ‘int main()’: user.cpp:19:31: 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:20:33: 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:22:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d\n",&n,&m); ^ user.cpp:42:18: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(v+1); ^ user.cpp:97:15: warning: ‘j2’ may be used uninitialized in this function [-Wmaybe-uninitialized] cd[1].y=j2; ^ user.cpp:96:15: warning: ‘j1’ may be used uninitialized in this function [-Wmaybe-uninitialized] cd[1].x=j1; ^ user.cpp:74:15: warning: ‘r2’ may be used uninitialized in this function [-Wmaybe-uninitialized] cd[1].y=r2; ^ user.cpp:73:15: warning: ‘r1’ may be used uninitialized in this function [-Wmaybe-uninitialized] cd[1].x=r1; ^ /tmp/cczL9xw3.o: In function `main': user.cpp:(.text.startup+0x140): warning: the `gets' function is dangerous and should not be used.