Compilare: main.cpp: In function 'int DFS(int)': main.cpp:18:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<v[u].size(); i++) ~^~~~~~~~~~~~ main.cpp:23:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ main.cpp: In function 'int main()': main.cpp:31:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("zapada.in", "r", stdin); ^ main.cpp:32:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("zapada.out", "w", stdout); ^ main.cpp:34:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m); ^ main.cpp:37:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &a, &b); ^ main.cpp:48:14: warning: 'last' may be used uninitialized in this function [-Wmaybe-uninitialized] DFS(last); ^