Compilare: user.cpp: In function ‘void DFS(int)’: user.cpp:19:14: warning: suggest parentheses around assignment used as truth value [-Wparentheses] viz[nod] = V[nod].sa = 1; ^ user.cpp:21:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < A[nod].size (); ++i) ^ user.cpp: In function ‘int main()’: user.cpp:46:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j = 0; j < A[i].size (); ++j) ^ user.cpp:34:18: warning: unused variable ‘n’ [-Wunused-variable] int i, a, b, n, m = 2e9, j, R[DMAX], s = 0; ^