/* [1] wo sankou ni shita ga (omoni median), warito tigau koto wo shita. Priority Queue wo tsukau to toptree wo tukawanaku temo ikeru ikeru (?) [1] S. Alstrup, J. Holm, K. D. Lichtenberg, M. Thorup. Maintaining information in fully dynamic trees with top trees, Jornal ACM Transactions on Algorithms, 1(2), Pages 243--264, 2005. */ #include #include #include /* priority_queue */ #include using namespace std; #define N 100001 #define TRUE 1 #define FALSE 0 void swap(int *x, int *y) { int t = *x; *x = *y; *y = t; } void swapl(long long *x, long long *y) { long long t = *x; *x = *y; *y = t; } struct Queue { std::priority_queue> q; std::priority_queue> q2; void ins(int k, int v) { q.emplace(k, v); } void del(int k, int v) { q2.emplace(k, v); } std::pair min() { while (!q.empty() && !q2.empty() && q.top() == q2.top()) { q.pop(); q2.pop(); } return q.top(); } int size() { return q.size() - q2.size(); } }; Queue q[N]; /* structure data */ int L[N], R[N], P[N], REV[N]; int MARKED[N]; /* whether the specified node is marked or not (this is a bool value) */ long long L_COST[N]; /* the cost of the downward edge */ long long R_COST[N]; /* the cost of the upward etge */ long long P_COST[N]; /* aggregation data */ int W[N]; /* the numebr of marked children */ long long WU[N]; /* the sum of weights from the external node named u to other nodes */ long long WV[N]; /* the sum of weights from the external node named v to other nodes */ long long WD[N]; /* the sum of weights from the central node to other nodes */ long long LEN[N]; /* the total length of the current cluster path */ /* special aggregation data (this data should be handled carefully !!) */ int W_DASHED[N]; /* the number of marked children lied on dashed subtrees */ long long WD_DASHED[N]; /* the sum of weights from the central node to the dashed children of the specified node */ /* external node, v is an ancestor of u */ void fix(int x) { W[x] = MARKED[x] + W_DASHED[x] + W[L[x]] + W[R[x]]; WD[x] = WD_DASHED[x] + WV[L[x]] + WU[R[x]] + W[L[x]] * L_COST[x] + W[R[x]] * R_COST[x]; WU[x] = WU[L[x]] + WU[R[x]] + WD_DASHED[x] + (LEN[L[x]] + L_COST[x]) * (MARKED[x] + W_DASHED[x]) + (LEN[L[x]] + L_COST[x] + R_COST[x]) * W[R[x]]; WV[x] = WV[R[x]] + WV[L[x]] + WD_DASHED[x] + (LEN[R[x]] + R_COST[x]) * (MARKED[x] + W_DASHED[x]) + (LEN[R[x]] + R_COST[x] + L_COST[x]) * W[L[x]]; LEN[x] = LEN[L[x]] + LEN[R[x]] + L_COST[x] + R_COST[x]; /* (^^) */ } void reverse(int x, int rev) { if (!rev) return; REV[x] ^= rev; swapl(&WU[x], &WV[x]); swapl(&L_COST[x], &R_COST[x]); swap(&L[x], &R[x]); } void push(int x) { reverse(L[x], REV[x]); reverse(R[x], REV[x]); REV[x] = FALSE; } void rot(int x) { int y = P[x]; int z = P[y]; if (L[z] == y) L[z] = x; if (R[z] == y) R[z] = x; P_COST[x] = P_COST[y]; P_COST[y] = 0; P[y] = x; P[x] = z; if (L[y] == x) { L[y] = R[x]; R[x] = y; if (L[y]) P[L[y]] = y; else { swapl(&L_COST[y], &R_COST[x]); } } else { R[y] = L[x]; L[x] = y; if (R[y]) P[R[y]] = y; else { swapl(&R_COST[y], &L_COST[x]); } } fix(y); } bool is_root(int x) { return L[P[x]] != x && R[P[x]] != x; } void local_splay(int x) { while (!is_root(x)) { if (!is_root(P[x])) { rot((L[P[x]] == x) == (L[P[P[x]]] == P[x]) ? P[x] : x); } rot(x); } } void push_ancestors(int x) { if (!x) return; push_ancestors(P[x]); push(x); } void global_splay(int x) { push_ancestors(x); { int y = x; while (y != 0) { while (!is_root(y)) y = P[y]; int z = P[y]; if (z) { W_DASHED[z] -= W[y]; WD_DASHED[z] -= WV[y] + W[y] * P_COST[y]; q[z].del(W[y], y); } y = z; } } int y = x; int l = 0; while (y != 0) { local_splay(y); int w = L[y]; P_COST[w] = L_COST[y]; L_COST[y] = P_COST[l]; P_COST[l] = 0; W_DASHED[y] += W[w]; WD_DASHED[y] += WV[w] + W[w] * P_COST[w]; if (w) { q[y].ins(W[w], w); } L[y] = l; l = y; fix(y); y = P[y]; } local_splay(x); fix(x); } void reroot(int x) { global_splay(x); reverse(x, TRUE); push(x); } void link(int x, int y, long long w) { reroot(x); global_splay(y); // assert(L[y] == 0); assert(P[x] == 0); L[y] = x; P[x] = y; L_COST[y] = w; fix(y); } void cut(int x, int y) { reroot(x); global_splay(y); R_COST[y] = 0; P_COST[R[y]] = 0; P[R[y]] = 0; R[y] = 0; fix(y); } void dfs(int u) { if (!u) { return; } dfs(L[u]); // assert(!(L[u] == 0 && L_COST[u] != 0)); // assert(!(R[u] == 0 && R_COST[u] != 0)); printf(" "); printf("(%d,%lld)", L[u], L_COST[u]); printf("%d", u); printf("(%d,%lld)", R[u], R_COST[u]); printf(" "); dfs(R[u]); } void iter(int x, vector &res) { if (!x) return; res.push_back(x); iter(L[x], res); iter(R[x], res); } bool same(int x, int y) { while (P[x] != 0) x = P[x]; while (P[y] != 0) y = P[y]; bool res = x == y; global_splay(x); global_splay(y); return res; } long long median2(int x, int n) { long long res = 2e18; for (int i = 1; i <= n; i++) { if (same(i, x)) { global_splay(i); res = min(res, WD[i]); } } return res; } pair median(int x) { global_splay(x); int ll = 0; int rr = 0; int E = W[x]; for (;;) { push(x); int n = W[x]; if (L[x]) { int y = L[x]; int ny = ll + W[y]; int nx = E - ny; assert(ny + nx == E); if (ny > nx) { rr += W[x] - W[y]; x = y; continue; } } if (R[x]) { int y = R[x]; int ny = rr + W[y]; int nx = E - ny; assert(ny + nx == E); if (ny > nx) { ll += W[x] - W[y]; x = y; continue; } } if (q[x].size() > 0) { int y = q[x].min().second; assert(is_root(y)); int ny = W[y]; int nx = E - ny; if (ny > nx) { rr += ll + W[x] - W[y]; ll = 0; x = y; continue; } } break; } global_splay(x); return make_pair(x, WD[x]); } void output(int n) { for (int i = 1; i <= n; i++) { global_splay(i); printf("%d %lld %lld\n", i, WD[i], LEN[i]); } for (int i = 1; i <= n; i++) { if (is_root(i)) { printf("*** %d %d\n", i, P[i]); } } for (int i = 1; i <= n; i++) { if (is_root(i)) { dfs(i); } puts(""); } } void test1() { for (int i = 1; i <= 7; i++) { MARKED[i] = 1; } link(1, 2, 2); link(3, 4, 4); link(2, 3, 3); link(5, 6, 3); link(5, 7, 10); link(2, 5, 1); printf("%d %d %d %d %lld %lld %lld %lld\n", L[0], R[0], P[0], W[0], WD[0], WU[0], WV[0], LEN[0]); reroot(1); for (int i = 1; i <= 7; i++) { global_splay(i); } for (int i = 1; i <= 7; i++) { printf("*** %d %lld\n", i, P_COST[i]); } global_splay(7); for (int i = 1; i <= 7; i++) { if (is_root(i)) { dfs(i); } puts(""); } global_splay(1); assert(WD[1] == 38); assert(W[1] == 7); global_splay(2); assert(WD[2] == 28); assert(W[2] == 7); global_splay(3); assert(WD[3] == 37); assert(W[3] == 7); global_splay(4); assert(WD[4] == 57); assert(W[4] == 7); global_splay(5); assert(WD[5] == 29); assert(W[5] == 7); global_splay(6); assert(WD[6] == 44); assert(W[6] == 7); global_splay(7); assert(WD[7] == 79); assert(W[7] == 7); cout << "---" << endl; cut(2, 5); for (int i = 1; i <= 7; i++) { printf("*** %d %lld\n", i, P_COST[i]); } for (int i = 1; i <= 7; i++) { if (is_root(i)) { dfs(i); } puts(""); } } void test2() { for (int i = 1; i <= 7; i++) { MARKED[i] = 1; } link(1, 2, 2); link(3, 4, 4); link(2, 5, 1); link(5, 6, 3); link(5, 7, 10); link(2, 3, 3); pair res = median(1); assert(res.first == 2 && res.second == 28); } long long Q; int main() { int n, q; scanf("%d %d", &n, &q); for (int i = 1; i <= n; i++) { MARKED[i] = TRUE; } long long S = 0; while (q--) { int type; scanf("%d", &type); if (type == 1) { int a, b, c; scanf("%d %d %d", &a, &b, &c); a = (a - 1 + S) % n + 1; b = (b - 1 + S) % n + 1; link(a, b, c); } else if (type == 2) { int a, b; scanf("%d %d", &a, &b); a = (a - 1 + S) % n + 1; b = (b - 1 + S) % n + 1; cut(a, b); } else { int a; scanf("%d", &a); a = (a - 1 + S) % n + 1; global_splay(a); MARKED[a] ^= 1; fix(a); long long ans = median(a).second; S += ans; S %= n; printf("%lld\n", ans); } } }