| #include <bits/stdc++.h> |
| using namespace std; |
|
|
| class FastScanner { |
| static constexpr size_t BUFSIZE = 1 << 20; |
| unsigned char buf[BUFSIZE]; |
| size_t idx = 0, size = 0; |
|
|
| inline bool refill() { |
| size = fread(buf, 1, BUFSIZE, stdin); |
| idx = 0; |
| return size > 0; |
| } |
|
|
| public: |
| template <class T> |
| bool readInt(T &out) { |
| out = 0; |
| T sign = 1; |
| unsigned char c; |
| do { |
| if (idx >= size && !refill()) return false; |
| c = buf[idx++]; |
| } while (c <= ' '); |
|
|
| if (c == '-') { |
| sign = -1; |
| if (idx >= size && !refill()) return false; |
| c = buf[idx++]; |
| } |
| for (; c > ' '; ) { |
| out = out * 10 + (c - '0'); |
| if (idx >= size) { |
| if (!refill()) break; |
| } |
| c = buf[idx++]; |
| } |
| out *= sign; |
| return true; |
| } |
| }; |
|
|
| int main() { |
| ios::sync_with_stdio(false); |
| cin.tie(nullptr); |
|
|
| FastScanner fs; |
| int n, m; |
| if (!fs.readInt(n)) return 0; |
| fs.readInt(m); |
|
|
| |
| for (int i = 0; i < 10; i++) { |
| int x; fs.readInt(x); |
| } |
|
|
| vector<int> head(n + 1, -1), rhead(n + 1, -1); |
| vector<int> to(m), nxt(m), rto(m), rnxt(m); |
| vector<int> outdeg(n + 1, 0); |
|
|
| for (int i = 0; i < m; i++) { |
| int u, v; |
| fs.readInt(u); fs.readInt(v); |
|
|
| to[i] = v; |
| nxt[i] = head[u]; |
| head[u] = i; |
|
|
| rto[i] = u; |
| rnxt[i] = rhead[v]; |
| rhead[v] = i; |
|
|
| outdeg[u]++; |
| } |
|
|
| int start = 1; |
| for (int v = 2; v <= n; v++) { |
| if (outdeg[v] > outdeg[start]) start = v; |
| } |
|
|
| vector<char> vis(n + 1, 0); |
| vector<int> outPtr = head, inPtr = rhead; |
|
|
| deque<int> path; |
| path.push_back(start); |
| vis[start] = 1; |
|
|
| int first = start, last = start; |
|
|
| bool progress = true; |
| while (progress) { |
| progress = false; |
|
|
| |
| while (true) { |
| int &e = outPtr[last]; |
| while (e != -1 && vis[to[e]]) e = nxt[e]; |
| if (e == -1) break; |
| int nx = to[e]; |
| e = nxt[e]; |
| if (!vis[nx]) { |
| vis[nx] = 1; |
| path.push_back(nx); |
| last = nx; |
| progress = true; |
| } |
| } |
|
|
| |
| while (true) { |
| int &e = inPtr[first]; |
| while (e != -1 && vis[rto[e]]) e = rnxt[e]; |
| if (e == -1) break; |
| int pr = rto[e]; |
| e = rnxt[e]; |
| if (!vis[pr]) { |
| vis[pr] = 1; |
| path.push_front(pr); |
| first = pr; |
| progress = true; |
| } |
| } |
| } |
|
|
| cout << path.size() << "\n"; |
| for (size_t i = 0; i < path.size(); i++) { |
| if (i) cout << ' '; |
| cout << path[i]; |
| } |
| cout << "\n"; |
| return 0; |
| } |
