Compilare: user.cpp: In function ‘void solve()’: user.cpp:51:17: warning: unused variable ‘ak’ [-Wunused-variable] int ak = 57; ^ user.cpp:59:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < V[nod].size(); ++ j) ^ user.cpp:85:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < V[v[i]].size(); ++ j) ^ user.cpp: In function ‘void read()’: user.cpp:20:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &n, &m); ^ user.cpp:24:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &x, &y); ^