#include #include #include using namespace std; struct BipartiteMatching { int n, timestamp; vector> graph; vector alive, used, match; BipartiteMatching(int n) : \ n(n), timestamp(0), graph(n), alive(n, 1), used(n, 0), match(n, -1) { } void add_edge(int u, int v) { graph[u].emplace_back(v); graph[v].emplace_back(u); } bool dfs(int idx) { used[idx] = timestamp; for (int to: graph[idx]) if (alive[to]) { int to_match = match[to]; if (to_match == -1 || (used[to_match] != timestamp && dfs(to_match))) { match[idx] = to; match[to] = idx; return true; } } return false; } int bipartite_matching() { int ret = 0; for (int i = 0; i < n; i++) if (alive[i]) { if (match[i] == -1) ++timestamp, ret += dfs(i); } return ret; } friend ostream& operator<<(ostream& os, BipartiteMatching& bm) { for (int i = 0; i < bm.n; i++) if (i < bm.match[i]) { os << i << " - " << bm.match[i] << endl; } return os; } }; int main() { int n; cin >> n; BipartiteMatching bm(n + n); for (int i = 0; i < n; i++) { int a; cin >> a; for (int j = 0; j < n; j++) if (j != a) bm.add_edge(i, j + n); } if (bm.bipartite_matching() == n) { for (int i = 0; i < n; i++) cout << bm.match[i] - n << endl; } else { cout << -1 << endl; } return 0; }