Compilare: user.cpp: In function ‘void read()’: user.cpp:42:13: warning: variable ‘z’ set but not used [-Wunused-but-set-variable] int x,y,z; ^ user.cpp: In function ‘int get()’: user.cpp:31:44: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] while(buff[ps]<'0' || buff[ps]>'9') nxt; ^ user.cpp:35:12: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] nxt; ^ user.cpp: In function ‘int main()’: user.cpp:246:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("arb4.in","r",stdin); ^ user.cpp:247:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("arb4.out","w",stdout); ^ user.cpp: In function ‘void dfs(int, int, int)’: user.cpp:74:17: warning: ‘node’ may be used uninitialized in this function [-Wmaybe-uninitialized] p[path[node]].pb(k),path[k]=path[node]; ^