#include #include #include #include using std::cin; using std::cout; using std::endl; const int N = 300005; int n, q, a[N], pre[N]; std::map map; // Segment Tree int cnt, root[N]; int build(int, int); int insert(int, int, int); int query(int, int); int main() { cin >> n; for (int i = 1; i <= n; i++) { cin >> a[i]; } root[0] = build(1, n); for (int i = 1; i <= n; i++) { if (!map.count(a[i])) { root[i] = insert(root[i - 1], i, 1); } else { int tmp = insert(root[i - 1], map[a[i]], -1); root[i] = insert(tmp, i, 1); } map[a[i]] = i; } cin >> q; while (q--) { int l, r; cin >> l >> r; cout << query(root[r], l) << endl; } return 0; } // === Segment Tree === struct node { int l, r, c; int lid, rid; node() : l(0), r(0), c(0), lid(0), rid(0) {} node(int _l, int _r) : l(_l), r(_r), c(0), lid(0), rid(0) {} } tr[N << 7]; inline void pushup(int u) { tr[u].c = tr[tr[u].lid].c + tr[tr[u].rid].c; } int build(int l, int r) { int p = ++cnt; tr[p] = node(l, r); if (l == r) return p; int mid = l + r >> 1; tr[p].lid = build(l, mid); tr[p].rid = build(mid + 1, r); return p; } int insert(int p, int x, int v) { int q = ++cnt; tr[q] = tr[p]; if (tr[q].l == tr[q].r) { tr[q].c += v; return q; } int mid = tr[q].l + tr[q].r >> 1; if (x <= mid) { tr[q].lid = insert(tr[p].lid, x, v); } else { tr[q].rid = insert(tr[p].rid, x, v); } pushup(q); return q; } int query(int u, int x) { if (tr[u].l == tr[u].r) return tr[u].c; int mid = tr[u].l + tr[u].r >> 1; if (x <= mid) return tr[tr[u].rid].c + query(tr[u].lid, x); return query(tr[u].rid, x); }