Compilare: user.cpp: In function ‘void Recurs(long int)’: user.cpp:38:52: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(long i=0;i<list[C[nod].xx][C[nod].yy].size();i++){ ^ user.cpp: In function ‘int main()’: user.cpp:48:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("mxl.in","r",stdin); ^ user.cpp:49:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("mxl.out","w",stdout); ^ user.cpp:51:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%ld%ld\n",&n,&m); ^ user.cpp:53:16: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s); pos = 0; lim = strlen(s); ^ /tmp/ccEbdj9H.o: In function `main': user.cpp:(.text.startup+0x88): warning: the `gets' function is dangerous and should not be used.