洛谷P3384 【模板】树链剖分

╰半橙微兮° 2023-08-17 17:21 51阅读 0赞

# 【模板】树链剖分 #

[题目传送门][Link 1]

## 代码如下 ##

#include <iostream> #include <cstdio> #include <vector> #define maxn 100005 using namespace std; typedef long long ll; struct T{ int data, next; }e[maxn << 1]; int top[maxn], son[maxn], size[maxn], depth[maxn], data[maxn], fa[maxn]; int head[maxn], cnt; vector<int> vec; int p; struct node{ int l, r; ll sum; ll lazy; }tree[maxn << 2]; void add(int x, int y) { ++ cnt; e[cnt].data = y; e[cnt].next = head[x]; head[x] = cnt; } void dfs1(int x) { size[x] = 1; for(int i = head[x]; i != 0; i = e[i].next){ int r = e[i].data; if(r != fa[x]){ depth[r] = depth[x] + 1; fa[r] = x; dfs1(r); size[x] += size[r]; if(!son[x] || size[r] > size[son[x]]) son[x] = r; } } } int mp[maxn]; void dfs2(int x, int k) { if(x == 0) return; top[x] = k; vec.push_back(x); mp[x] = vec.size() - 1; dfs2(son[x], k); for(int i = head[x]; i != 0; i = e[i].next){ int r = e[i].data; if(r != fa[x] && r != son[x]){ dfs2(r, r); } } } void build(int l, int r, int k) { tree[k].l = l; tree[k].r = r; if(l == r){ tree[k].sum = data[vec[l]]; return; } int mid = (l + r) / 2; build(l, mid, 2*k); build(mid + 1, r, 2*k+1); tree[k].sum = tree[2*k].sum + tree[2*k+1].sum; tree[k].sum %= p; } void down(int k) { if(tree[k].lazy == 0) return; tree[2*k].sum += (tree[2*k].r - tree[2*k].l + 1) * tree[k].lazy; tree[2*k+1].sum += (tree[2*k+1].r - tree[2*k+1].l + 1) * tree[k].lazy; tree[2*k].lazy += tree[k].lazy; tree[2*k + 1].lazy += tree[k].lazy; tree[k].lazy = 0; } void add(int l, int r, int z, int k) { if(tree[k].l >= l && tree[k].r <= r){ tree[k].sum += ((tree[k].r - tree[k].l + 1) * z) % p; tree[k].sum %= p; tree[k].lazy += z; return; } down(k); int mid = (tree[k].l + tree[k].r) / 2; if(l <= mid) add(l, r, z, 2*k); if(r > mid) add(l, r, z, 2*k+1); tree[k].sum = tree[2*k].sum + tree[2*k + 1].sum; tree[k].sum %= p; } void add1(int x, int y, int z) { while(top[x] != top[y]){ if(depth[top[x]] > depth[top[y]]){ add(mp[top[x]], mp[x], z, 1); x = fa[top[x]]; } else { add(mp[top[y]], mp[y], z, 1); y = fa[top[y]]; } } if(depth[x] > depth[y]) add(mp[y], mp[x], z, 1); else add(mp[x], mp[y], z, 1); } ll query(int l, int r, int k) { if(tree[k].l >= l && tree[k].r <= r){ return tree[k].sum; } down(k); int mid = (tree[k].l + tree[k].r) / 2; ll ans = 0; if(l <= mid) ans += query(l, r, 2*k), ans %= p; if(r > mid) ans += query(l, r, 2*k+1), ans %= p;; return ans; } ll get1(int x, int y) { ll ans = 0; while(top[x] != top[y]){ if(depth[top[x]] > depth[top[y]]){ ans += query(mp[top[x]], mp[x], 1); ans %= p; x = fa[top[x]]; } else { ans += query(mp[top[y]], mp[y], 1); ans %= p; y = fa[top[y]]; } } if(depth[x] > depth[y]) ans += query(mp[y], mp[x], 1), ans %= p; else ans += query(mp[x], mp[y], 1), ans %= p; return ans; } inline void add2(int x, int y) { add(mp[x], mp[x] + size[x] - 1, y, 1); } inline ll get2(int x) { return query(mp[x], mp[x] + size[x] - 1, 1) % p; } int main() { int n, m, r; scanf("%d%d%d%d", &n, &m, &r, &p); for(int i = 1; i <= n; i ++) scanf("%d", &data[i]); for(int i = 1; i < n; i ++){ int x, y; scanf("%d%d", &x, &y); add(x, y); add(y, x); } vec.push_back(0); dfs1(r); dfs2(r, r); build(1, n, 1); for(int i = 1; i <= m; i ++){ int opt; scanf("%d", &opt); if(opt == 1){ int x, y, z; scanf("%d%d%d", &x, &y, &z); add1(x, y, z); } else if(opt == 2){ int x, y; scanf("%d%d", &x, &y); printf("%lld\n", get1(x, y) % p); } else if(opt == 3){ int x, y; scanf("%d%d", &x, &y); add2(x, y); } else { int x; scanf("%d", &x); printf("%lld\n", get2(x) % p); } } return 0; }

转载于:https://www.cnblogs.com/whisperlzw/p/11420657.html

[Link 1]: https://www.luogu.org/problem/P3384