P3806 【模板】点分治 1
#include <bits/stdc++.h>
using namespace std;inline long long read() {char ch = getchar();long long f = 1,x = 0;while (ch > '9' || ch < '0') { if (ch == '-')f = -1; ch = getchar(); }while (ch >= '0' && ch <= '9') { x = (x << 1) + (x << 3) + ch - '0'; ch = getchar(); }return x * f;
}
//void ReadFile() {
// FILE* stream1;
// freopen_s(&stream1,"in.txt", "r", stdin);
// freopen_s(&stream1,"out.txt", "w", stdout);
//}static auto speedup = []() {ios::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr); return nullptr; }();const int maxn = 1e4 + 7,INF = 1e7 + 7;
bitset<INF> judge;int n,m,vis[maxn],sum = 0,subsum = 0,root = 0, ask[maxn],ans[maxn],siz[maxn],d[maxn],dis[maxn],cnt;
int q[INF];struct Node {Node() :y(0), dis(0){}Node(int a,int b) :y(a), dis(b) {}int y,dis;
};
vector<Node> e[maxn];void getroot(int x, int fa) {siz[x] = 1;int s = 0;for (auto& nx : e[x]) {if (nx.y == fa || vis[nx.y])continue;getroot(nx.y, x);siz[x] += siz[nx.y];s = max(s, siz[nx.y]);}s = max(s, sum - siz[x]);if (s < subsum) {root = x;subsum = s;}}
void getdis(int x, int fa) {dis[++cnt] = d[x];for (auto& nx : e[x]) {if (nx.y == fa || vis[nx.y])continue;d[nx.y] = d[x] + nx.dis;getdis(nx.y, x);}
}void calc(int x) {judge[0] = 1;int p = 0;for (auto& nx : e[x]) {if (vis[nx.y])continue;cnt = 0;d[nx.y] = nx.dis;getdis(nx.y, x);for (int j = 1; j <= cnt; j++) {for (int k = 1; k <= m; k++) {if (ask[k] >= dis[j]) {ans[k] |= judge[ask[k] - dis[j]];}}}for (int j = 1; j <= cnt; j++) {if (dis[j] < INF) {q[++p] = dis[j];judge[dis[j]] = 1;}}}for (int i = 1; i <= p; i++)judge[q[i]] = 0;
}void divide(int x) {calc(x);vis[x] = 1;for (auto& nx : e[x]) {if (vis[nx.y])continue;sum = subsum = siz[nx.y];getroot(nx.y,0);divide(root);}
}
void slove() {cin >> n >> m;int a, b, c;for (int i = 1; i < n; i++) {cin >> a >> b >> c;e[a].push_back(Node{ b,c });e[b].push_back(Node{ a,c });}for (int i = 1; i <= m; i++) {cin >> ask[i];}sum = subsum = n;getroot(1, 0);getroot(root, 0);divide(root);for (int i = 1; i <= m; i++) {cout << (ans[i] ? "AYE" : "NAY") << endl;}
}
int main() {slove();return 0;
}
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