1 struct Tree 2 { 3 int n, a[maxn]; 4 5 struct Edge 6 { 7 int v, next; 8 }edge[maxn<<1]; 9 10 int head[maxn], tot; 11 12 void add(int u, int v) 13 { 14 edge[tot].v = v; 15 edge[tot].next = head[u]; 16 head[u] = tot++; 17 } 18 19 int fa[maxn], deep[maxn], son[maxn], size[maxn]; 20 int top[maxn], id[maxn], rk[maxn]; 21 int cnt; 22 23 void dfs1(int x, int pre, int d) 24 { 25 size[x] = 1, deep[x] = d, fa[x] = pre; 26 for (int i = head[x]; i != -1; i = edge[i].next) 27 { 28 int v = edge[i].v; 29 if (v == pre) continue; 30 dfs1(v, x, d + 1); 31 size[x] += size[v]; 32 if (size[v] > size[son[x]]) son[x] = v; 33 } 34 } 35 36 void dfs2(int x, int tp) 37 { 38 top[x] = tp, id[x] = ++cnt, rk[cnt] = x; 39 if (son[x]) dfs2(son[x], tp); 40 for (int i = head[x]; i != -1; i = edge[i].next) 41 { 42 int v = edge[i].v; 43 if (v == fa[x] || v == son[x]) continue; 44 dfs2(v, v); 45 } 46 } 47 48 int sum[maxn << 2], lazy[maxn << 2]; 49 50 void push_up(int rt) 51 { 52 sum[rt] = (sum[ls] + sum[rs]); 53 } 54 55 void push_down(int rt,int l,int r) 56 { 57 int mid = (l + r) >> 1; 58 sum[ls] += lazy[rt] * (mid - l + 1); 59 sum[rs] += lazy[rt] * (r - mid); 60 lazy[ls] += lazy[rt]; 61 lazy[rs] += lazy[rt]; 62 lazy[rt] = 0; 63 } 64 65 void build(int rt, int l, int r) 66 { 67 if (l == r) 68 { 69 sum[rt] = a[rk[l]]; 70 return; 71 } 72 int mid = (l + r) >> 1; 73 build(ls,l,mid); 74 build(rs,mid+1,r); 75 push_up(rt); 76 } 77 78 void update(int rt, int l, int r, int ql, int qr, int val) 79 { 80 if (ql <= l && qr >= r) 81 { 82 lazy[rt] += val; 83 sum[rt] += val * (r - l + 1); 84 return; 85 } 86 push_down(rt, l, r); 87 int mid = (l + r) >> 1; 88 if (ql <= mid) update(ls, l, mid, ql, qr, val); 89 if (qr > mid) update(rs, mid + 1, r, ql, qr, val); 90 push_up(rt); 91 } 92 93 int query(int rt, int l, int r, int ql, int qr) 94 { 95 if (ql <= l && qr >= r) 96 { 97 return sum[rt]; 98 } 99 push_down(rt, l, r); 100 int mid = (l + r) >> 1; 101 int res = 0; 102 if (ql <= mid) res += query(ls, l, mid, ql, qr); 103 if (qr > mid) res += query(rs, mid + 1, r, ql, qr); 104 return res; 105 } 106 107 int getSum(int x, int y) 108 { 109 int res = 0; 110 while (top[x] != top[y]) 111 { 112 if (deep[x] < deep[y]) swap(x, y); 113 res += query(1, 1, n, id[top[x]], id[x]); 114 x = fa[top[x]]; 115 } 116 if (id[x] > id[y]) swap(x, y); 117 return res + query(1, 1, n, id[x], id[y]); 118 } 119 120 void Update(int x, int y, int val) 121 { 122 while (top[x] != top[y]) 123 { 124 if (deep[top[x]] < deep[top[y]]) swap(x, y); 125 update(1, 1, n, id[top[x]], id[x], val); 126 x = fa[top[x]]; 127 } 128 if (id[x] > id[y]) swap(x, y); 129 update(1, 1, n, id[x], id[y], val); 130 } 131 132 void init() 133 { 134 memset(head, -1, sizeof head); 135 tot = 0, cnt = 0; 136 memset(lazy, 0, sizeof lazy); 137 memset(sum, 0, sizeof sum); 138 memset(son, 0, sizeof son); 139 } 140 };