（1） KD树，但实际没有STL快，3000+
1 /* 4400 */ 2 #include <iostream> 3 #include <string> 4 #include <map> 5 #include <queue> 6 #include <set> 7 #include <stack> 8 #include <vector> 9 #include <deque> 10 #include <algorithm> 11 #include <cstdio> 12 #include <cmath> 13 #include <ctime> 14 #include <cstring> 15 #include <climits> 16 #include <cctype> 17 #include <cassert> 18 #include <functional> 19 #include <iterator> 20 #include <iomanip> 21 using namespace std; 22 //#pragma comment(linker,"/STACK:102400000,1024000") 23 24 #define sti set<int> 25 #define stpii set<pair<int, int> > 26 #define mpii map<int,int> 27 #define vi vector<int> 28 #define pii pair<int,int> 29 #define vpii vector<pair<int,int> > 30 #define rep(i, a, n) for (int i=a;i<n;++i) 31 #define per(i, a, n) for (int i=n-1;i>=a;--i) 32 #define clr clear 33 #define pb push_back 34 #define mp make_pair 35 #define fir first 36 #define sec second 37 #define all(x) (x).begin(),(x).end() 38 #define SZ(x) ((int)(x).size()) 39 #define lson l, mid, rt<<1 40 #define rson mid+1, r, rt<<1|1 41 42 typedef struct Point_t { 43 int x, y, d, id; 44 45 Point_t() {} 46 Point_t(int x, int y, int d, int id): 47 x(x), y(y), d(d), id(id) {} 48 49 } Point_t; 50 51 typedef struct node_t{ 52 int axis; 53 int id; 54 int l, r; 55 } node_t; 56 57 const int maxn = 1e5+5; 58 Point_t P[maxn]; 59 node_t nd[maxn]; 60 bool visit[maxn]; 61 int Q[maxn]; 62 int L, head, tail; 63 64 bool compx(const Point_t& a, const Point_t& b) { 65 return a.x < b.x; 66 } 67 68 bool compy(const Point_t& a, const Point_t& b) { 69 return a.y < b.y; 70 } 71 72 bool compid(const Point_t& a, const Point_t& b) { 73 return a.id < b.id; 74 } 75 76 int newNode() { 77 ++L; 78 nd[L].l = nd[L].r = 0; 79 80 return L; 81 } 82 83 int create(int l, int r, int d) { 84 if (l > r) return 0; 85 86 int rt = newNode(); 87 nd[rt].axis = d & 1; 88 if (l == r) { 89 nd[rt].id = P[l].id; 90 return rt; 91 } 92 93 if (d & 1) { 94 sort(P+l, P+r+1, compy); 95 } else { 96 sort(P+l, P+r+1, compx); 97 } 98 99 int mid = (l + r) >> 1; 100 101 nd[rt].id = P[mid].id; 102 nd[rt].l = create(l, mid-1, d+1); 103 nd[rt].r = create(mid+1, r, d+1); 104 105 return rt; 106 } 107 108 int Distance(int i, int j) { 109 return abs(P[i].x-P[j].x) + abs(P[i].y-P[j].y); 110 } 111 112 void search(int rt, int kth) { 113 if (rt == 0) 114 return ; 115 116 int i, j, k; 117 int id = nd[rt].id; 118 int dis = Distance(id, kth); 119 120 if (dis <= P[kth].d) { 121 if (!visit[id]) { 122 visit[id] = true; 123 Q[tail++] = id; 124 } 125 } 126 127 if (nd[rt].axis) { 128 // y 129 if (dis <= P[kth].d) { 130 search(nd[rt].l, kth); 131 search(nd[rt].r, kth); 132 } else { 133 int dy = abs(P[id].y - P[kth].y); 134 if (dy > P[kth].d) { 135 if (P[id].y <= P[kth].y) 136 search(nd[rt].r, kth); 137 else 138 search(nd[rt].l, kth); 139 } else { 140 search(nd[rt].l, kth); 141 search(nd[rt].r, kth); 142 } 143 } 144 145 } else { 146 147 // x 148 if (dis <= P[kth].d) { 149 search(nd[rt].l, kth); 150 search(nd[rt].r, kth); 151 } else { 152 int dx = abs(P[id].x - P[kth].x); 153 if (dx > P[kth].d) { 154 if (P[id].x <= P[kth].x) 155 search(nd[rt].r, kth); 156 else 157 search(nd[rt].l, kth); 158 } else { 159 search(nd[rt].l, kth); 160 search(nd[rt].r, kth); 161 } 162 } 163 } 164 } 165 166 void init() { 167 L = 0; 168 memset(visit, false, sizeof(visit)); 169 } 170 171 int solve(int rt, int k) { 172 if (visit[k]) 173 return 0; 174 175 head = tail = 0; 176 visit[k] = true; 177 Q[tail++] = k; 178 179 while (head < tail) { 180 search(rt, Q[head++]); 181 } 182 183 return tail; 184 } 185 186 int main() { 187 ios::sync_with_stdio(false); 188 #ifndef ONLINE_JUDGE 189 freopen("data.in", "r", stdin); 190 freopen("data.out", "w", stdout); 191 #endif 192 193 int t = 0; 194 int n, q; 195 int kth, ans; 196 197 while (scanf("%d", &n)!=EOF && n) { 198 rep(i, 0, n) { 199 scanf("%d %d %d", &P[i].x, &P[i].y, &P[i].d); 200 P[i].id = i; 201 } 202 init(); 203 int rt = create(0, n-1, 0); 204 sort(P, P+n, compid); 205 scanf("%d", &q); 206 printf("Case #%d: ", ++t); 207 while (q--) { 208 scanf("%d", &kth); 209 ans = solve(rt, kth-1); 210 printf("%d ", ans); 211 } 212 } 213 214 215 #ifndef ONLINE_JUDGE 216 printf("time = %d. ", (int)clock()); 217 #endif 218 219 return 0; 220 }
（2） STL 1400+
1 /* 4400 */ 2 #include <iostream> 3 #include <string> 4 #include <map> 5 #include <queue> 6 #include <set> 7 #include <stack> 8 #include <vector> 9 #include <deque> 10 #include <algorithm> 11 #include <cstdio> 12 #include <cmath> 13 #include <ctime> 14 #include <cstring> 15 #include <climits> 16 #include <cctype> 17 #include <cassert> 18 #include <functional> 19 #include <iterator> 20 #include <iomanip> 21 using namespace std; 22 //#pragma comment(linker,"/STACK:102400000,1024000") 23 24 #define sti set<int> 25 #define stpii set<pair<int, int> > 26 #define mpii map<int,int> 27 #define vi vector<int> 28 #define pii pair<int,int> 29 #define vpii vector<pair<int,int> > 30 #define rep(i, a, n) for (int i=a;i<n;++i) 31 #define per(i, a, n) for (int i=n-1;i>=a;--i) 32 #define clr clear 33 #define pb push_back 34 #define mp make_pair 35 #define fir first 36 #define sec second 37 #define all(x) (x).begin(),(x).end() 38 #define SZ(x) ((int)(x).size()) 39 #define lson l, mid, rt<<1 40 #define rson mid+1, r, rt<<1|1 41 42 typedef struct node_t { 43 int x, y, d; 44 45 node_t() {} 46 node_t(int x, int y, int d): 47 x(x), y(y), d(d) {} 48 49 friend bool operator< (const node_t& a, const node_t& b) { 50 return a.y < b.y; 51 } 52 53 } node_t; 54 55 typedef struct { 56 int y, id; 57 } pair_t; 58 59 const int maxn = 1e5+5; 60 int X[maxn]; 61 bool visit[maxn]; 62 node_t nd[maxn]; 63 vector< pii > vc[maxn]; 64 int n, m; 65 66 bool comp(const node_t& a, const node_t& b) { 67 return a.y < b.y; 68 } 69 70 void init() { 71 memset(visit, false, sizeof(visit)); 72 73 rep(i, 0, n) { 74 X[i] = nd[i].x; 75 vc[i].clr(); 76 } 77 78 sort(X, X+n); 79 m = unique(X, X+n) - X; 80 node_t tmp; 81 82 rep(i, 0, n) { 83 int id = lower_bound(X, X+m, nd[i].x) - X; 84 vc[id].pb(mp(nd[i].y, i)); 85 } 86 87 rep(i, 0, m) 88 sort(all(vc[i])); 89 } 90 91 int bfs(int kth) { 92 if (visit[kth]) 93 return 0; 94 95 int ret = 1; 96 int x, y, dx, dy; 97 int lx, rx, ly, ry; 98 int id, xid; 99 vector< pii >::iterator iter, liter, riter; 100 queue<int> Q; 101 pii p; 102 103 visit[kth] = true; 104 Q.push(kth); 105 p.sec = -1; 106 107 while (!Q.empty()) { 108 kth = Q.front(); 109 Q.pop(); 110 id = lower_bound(X, X+m, nd[kth].x) - X; 111 lx = lower_bound(X, X+m, nd[kth].x - nd[kth].d) - X; 112 rx = upper_bound(X, X+m, nd[kth].x + nd[kth].d) - X;; 113 for (xid=lx; xid<rx; ++xid) { 114 x = X[xid]; 115 dx = abs(x - nd[kth].x); 116 dy = nd[kth].d - dx; 117 ly = nd[kth].y - dy; 118 ry = nd[kth].y + dy; 119 120 // find lower_bound 121 p.fir = ly; 122 p.sec = -1; 123 liter = lower_bound(all(vc[xid]), p); 124 125 // find upper_bound 126 p.fir = ry; 127 p.sec = maxn; 128 riter = upper_bound(all(vc[xid]), p); 129 130 for (iter=liter; iter!=riter; ++iter) { 131 int k = iter->sec; 132 if (!visit[k]) { 133 visit[k] = true; 134 ++ret; 135 Q.push(k); 136 } 137 } 138 139 // vc[xid].erase(liter, riter); 140 } 141 } 142 143 return ret; 144 } 145 146 int main() { 147 ios::sync_with_stdio(false); 148 #ifndef ONLINE_JUDGE 149 freopen("data.in", "r", stdin); 150 freopen("data.out", "w", stdout); 151 #endif 152 153 int q; 154 int t = 0; 155 int ans; 156 157 while (scanf("%d", &n)!=EOF && n) { 158 rep(i, 0, n) 159 scanf("%d %d %d", &nd[i].x, &nd[i].y, &nd[i].d); 160 init(); 161 scanf("%d", &q); 162 printf("Case #%d: ", ++t); 163 int kth; 164 while (q--) { 165 scanf("%d", &kth); 166 --kth; 167 ans = bfs(kth); 168 printf("%d ", ans); 169 } 170 } 171 172 #ifndef ONLINE_JUDGE 173 printf("time = %d. ", (int)clock()); 174 #endif 175 176 return 0; 177 }