线段树的简单题目，做一个离散化，O（lgn）可以找到id。RE了一晚上，额，后来找到了原因。
1 /* 555C */
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 {
43 int x, y;
44 char op[4];
45 } node_t;
46
47 const int maxn = 2e5+5;
48 const int maxm = 4e5+5;
49 node_t Q[maxn];
50 int rn[maxm];
51 int mxr[maxm<<2];
52 int mxc[maxm<<2];
53 int rL[maxm<<2];
54 int cT[maxm<<2];
55 int L, R;
56
57 void build(int l, int r, int rt) {
58 rL[rt] = 1;
59 cT[rt] = 1;
60 if (l == r)
61 return ;
62
63 int mid = (l+r)>>1;
64 build(lson);
65 build(rson);
66 }
67
68 inline void PushDownR(int rt) {
69 int lb = rt<<1;
70 int rb = lb | 1;
71
72 if (mxr[rt]) {
73 rL[rt] = max(rL[rt], mxr[rt]);
74 mxr[lb] = max(mxr[lb], mxr[rt]);
75 mxr[rb] = max(mxr[rb], mxr[rt]);
76 mxr[rt] = 0;
77 }
78 }
79
80 inline void PushDownC(int rt) {
81 int lb = rt<<1;
82 int rb = lb | 1;
83
84 if (mxc[rt]) {
85 cT[rt] = max(cT[rt], mxc[rt]);
86 mxc[lb] = max(mxc[lb], mxc[rt]);
87 mxc[rb] = max(mxc[rb], mxc[rt]);
88 mxc[rt] = 0;
89 }
90 }
91
92 inline void PushDown(int rt) {
93 int lb = rt<<1;
94 int rb = lb | 1;
95
96 if (mxr[rt]) {
97 rL[rt] = max(rL[rt], mxr[rt]);
98 mxr[lb] = max(mxr[lb], mxr[rt]);
99 mxr[rb] = max(mxr[rb], mxr[rt]);
100 mxr[rt] = 0;
101 }
102
103 if (mxc[rt]) {
104 cT[rt] = max(cT[rt], mxc[rt]);
105 mxc[lb] = max(mxc[lb], mxc[rt]);
106 mxc[rb] = max(mxc[rb], mxc[rt]);
107 mxc[rt] = 0;
108 }
109 }
110
111 void updateR(int delta, int l, int r, int rt) {
112 if (L<=l && R>=r) {
113 mxr[rt] = max(mxr[rt], delta);
114 return ;
115 }
116
117 int mid = (l+r)>>1;
118
119 PushDownR(rt);
120 if (mid >= R) {
121 updateR(delta, lson);
122 } else if (mid < L) {
123 updateR(delta, rson);
124 } else {
125 updateR(delta, lson);
126 updateR(delta, rson);
127 }
128 }
129
130 void updateC(int delta, int l, int r, int rt) {
131 if (L<=l && R>=r) {
132 mxc[rt] = max(mxc[rt], delta);
133 return ;
134 }
135
136 int mid = (l+r)>>1;
137
138 PushDownC(rt);
139 if (mid >= R) {
140 updateC(delta, lson);
141 } else if (mid < L) {
142 updateC(delta, rson);
143 } else {
144 updateC(delta, lson);
145 updateC(delta, rson);
146 }
147 }
148
149 pii query(int l, int r, int rt) {
150 if (l == r) {
151 rL[rt] = max(rL[rt], mxr[rt]);
152 cT[rt] = max(cT[rt], mxc[rt]);
153 mxr[rt] = 0;
154 mxc[rt] = 0;
155
156 pii p(rL[rt], cT[rt]);
157 return p;
158 }
159 int mid = (l+r)>>1;
160
161 PushDown(rt);
162 if (mid >= R) {
163 return query(lson);
164 } else {
165 return query(rson);
166 }
167 }
168
169 int main() {
170 ios::sync_with_stdio(false);
171 #ifndef ONLINE_JUDGE
172 freopen("data.in", "r", stdin);
173 freopen("data.out", "w", stdout);
174 #endif
175
176 int n, q;
177 mpii tb;
178 sti st;
179
180 scanf("%d %d", &n, &q);
181 rep(i, 0, q) {
182 scanf("%d %d %s", &Q[i].y, &Q[i].x, Q[i].op);
183 st.insert(Q[i].x);
184 st.insert(Q[i].y);
185 }
186 st.insert(1);
187
188 int m = 0;
189 int i, j, k;
190
191 for (sti::iterator siter=st.begin(); siter!=st.end(); ++siter) {
192 k = *siter;
193 ++m;
194 rn[m] = k;
195 tb[k] = m;
196 }
197
198 int x, y, idx, idy;
199 int ans;
200 pii p;
201
202 build(1, m, 1);
203 rep(i, 0, q) {
204 x = Q[i].x;
205 y = Q[i].y;
206 if (Q[i].op[0] == ‘U‘) {
207 idy = tb[y];
208 L = R = idy;
209 p = query(1, m, 1);
210 updateC(x+1, 1, m, 1);
211 ans = x - p.sec + 1;
212 idx = tb[x];
213 k = lower_bound(rn+1, rn+1+m, p.sec) - rn;
214 L = k;
215 R = idx;
216 if (L <= R)
217 updateR(y+1, 1, m, 1);
218 } else {
219 idx = tb[x];
220 L = R = idx;
221 p = query(1, m, 1);
222 updateR(y+1, 1, m, 1);
223 ans = y - p.fir + 1;
224 idy = tb[y];
225 k = lower_bound(rn+1, rn+1+m, p.fir) - rn;
226 L = k;
227 R = idy;
228 if (L <= R)
229 updateC(x+1, 1, m, 1);
230 }
231 #ifndef ONLINE_JUDGE
232 printf("L = %d, R = %d\n", L, R);
233 #endif
234 if (ans < 0)
235 ans = 0;
236 printf("%d\n", ans);
237 }
238
239 #ifndef ONLINE_JUDGE
240 printf("time = %d.\n", (int)clock());
241 #endif
242
243 return 0;
244 }
时间： 2024-10-18 20:15:49