BZOJ1935: [Shoi2007]Tree 園丁的煩惱(樹狀陣列 二維數點)
阿新 • • 發佈:2019-01-03
題意
Sol
二維數點板子題
首先把詢問拆成四個矩形
然後離散化+樹狀陣列統計就可以了
#include<bits/stdc++.h> #define int long long #define LL long long using namespace std; const int MAXN = 1e6 + 10, mod = 1e9 + 7, INF = 3e18 + 10; const double eps = 1e-9; template <typename A, typename B> inline bool chmin(A &a, B b){if(a > b) {a = b; return 1;} return 0;} template <typename A, typename B> inline bool chmax(A &a, B b){if(a < b) {a = b; return 1;} return 0;} template <typename A> inline void debug(A a){cout << a << '\n';} inline int read() { char c = getchar(); int x = 0, f = 1; while(c < '0' || c > '9') {if(c == '-') f = -1; c = getchar();} while(c >= '0' && c <= '9') x = x * 10 + c - '0', c = getchar(); return x * f; } int N, T, fa[MAXN], d[MAXN], pp[MAXN], qq[MAXN], lim[MAXN], siz[MAXN], Sum, vis[MAXN], Mx, root, f[MAXN], st[MAXN], top, cnt; vector<int> v[MAXN]; void dfs(int x) { d[x] += d[fa[x]]; siz[x] = 1; for(int i = 0; i < v[x].size(); i++) { int to = v[x][i]; if(to == fa[x]) continue; dfs(to); siz[x] += siz[to]; } } void Find(int x) { //printf("%d\n", x); int mx = 0; siz[x] = 1; for(int i = 0; i < v[x].size(); i++) { int to = v[x][i]; if(to == fa[x] || vis[to]) continue; Find(to); siz[x] += siz[to]; chmax(mx, siz[to]); } chmax(mx, Sum - siz[x]); if(mx < Mx && siz[x] > 1) Mx = mx, root = x; } struct Node { int id, dis; bool operator < (const Node &rhs) const { return dis > rhs.dis; } }a[MAXN]; void dfs2(int x) { a[++cnt].id = x; a[cnt] = (Node) {x, d[x] - lim[x]}; for(int i = 0; i < v[x].size(); i++) { int to = v[x][i]; if(to == fa[x] || vis[to]) continue; dfs2(to); } } int Y(int x) { return f[x]; } int X(int x) { return d[x]; } double slope(int x, int y) { return (double) (Y(y) - Y(x)) / (X(y) - X(x)); } void insert(int x) { while(top > 1 && slope(st[top], x) > slope(st[top - 1], st[top])) top--; st[++top] = x; } int Search(double x, int id) { if(!top) return INF; int l = 1, r = top - 1, ans = 1; while(l <= r) { int mid = l + r >> 1; if((slope(st[mid], st[mid + 1]) >= x)) ans = mid + 1, l = mid + 1; else r = mid - 1; } return f[st[ans]] - d[st[ans]] * pp[id]; } void solve(int x, int tot, int up) { vector<int> pot; for(int t = x; t != up; t = fa[t]) pot.push_back(t); cnt = 0; for(int i = 0; i < v[x].size(); i++) { int to = v[x][i]; if(to == fa[x]) continue; dfs2(to);//dep´Ó´óµ½´ïС£¬dis´Ó´óµ½Ð¡ } sort(a + 1, a + cnt + 1); int now = 0; top = 0; for(int i = 1; i <= cnt; i++) { int cur = a[i].id; while(now <= pot.size() - 1 && d[pot[now]] >= a[i].dis) insert(pot[now++]); chmin(f[cur], Search(pp[cur], cur) + qq[cur] + d[cur] * pp[cur]); } } void work(int x, int tot) { if(tot == 1) return ; root = x; Sum = tot; Mx = Sum; Find(root); int rt = root; for(int i = 0; i < v[rt].size(); i++) { int to = v[rt][i]; if(to == fa[rt]) continue; vis[to] = 1; } work(x, tot - siz[root] + 1); solve(rt, tot, fa[x]); for(int i = 0; i < v[rt].size(); i++) { int to = v[rt][i]; if(to == fa[rt]) continue; work(to, siz[to]); } } signed main() { //freopen("a.in", "r", stdin); N = read(); T = read(); for(int i = 2; i <= N; i++) { fa[i] = read(); v[fa[i]].push_back(i); v[i].push_back(fa[i]); d[i] = read(); pp[i] = read(); qq[i] = read(); lim[i] = read(); } dfs(1); memset(f, 0x7f7f7f, sizeof(f)); f[1] = 0; work(1, N); for(int i = 2; i <= N; i++) cout << f[i] << '\n'; return 0; } /* 7 3 1 2 20 0 3 1 5 10 100 5 2 4 10 10 10 2 9 1 100 10 3 5 20 100 10 4 4 20 0 10 */