hdu 3577 线段树

题意：一列经过1000000个站点的火车上最多同时乘坐 K 个人，有 Q 个乘客按照题目给出的顺序去买票，输出所有购票成功的乘客

做法：RMQ线段树 + 区间更新

  1 #include "bits/stdc++.h"
  2 using namespace std;
  3 #define lson l, m, rt<<1
  4 #define rson m + 1, r, rt<<1|1
  5 const int MAXN = 1000010;
  6 const int INF = 0x3f3f3f3f;
  7
  8 struct Node
  9 {
 10     int Max;
 11
 12     int add;
 13     bool same;
 14     int sameVal;
 15 }node[MAXN<<2];
 16
 17 inline void PushDown(int rt, int segLen)
 18 {
 19     if (node[rt].same) {
 20         node[rt<<1].Max = node[rt].sameVal;
 21         node[rt<<1|1].Max = node[rt].sameVal;
 22
 23         node[rt<<1].same = node[rt<<1|1].same = true;
 24         node[rt<<1].sameVal = node[rt<<1|1].sameVal = node[rt].sameVal;
 25         node[rt].same = false;
 26     }
 27     if(node[rt].add) {
 28         node[rt<<1].Max += node[rt].add;
 29         node[rt<<1|1].Max += node[rt].add;
 30
 31         node[rt<<1].add += node[rt].add;
 32         node[rt<<1|1].add += node[rt].add;
 33         node[rt].add = 0;
 34     }
 35 }
 36
 37 inline void PushUp(int rt)
 38 {
 39     node[rt].Max = max(node[rt<<1].Max, node[rt<<1|1].Max);
 40 }
 41
 42 void Build(int l, int r, int rt)
 43 {
 44     node[rt].same = false;
 45     node[rt].add = 0;
 46
 47     if (l == r) {
 48 //        scanf("%d", &node[rt].Max);
 49         node[rt].Max = 0;
 50         return ;
 51     }
 52     int m = (l + r)>>1;
 53     Build(lson);
 54     Build(rson);
 55
 56     PushUp(rt);
 57 }
 58
 59 void UpdateAdd(int p, int add, int l, int r, int rt)
 60 {
 61     if (l == r) {
 62         node[rt].Max += add;
 63         return ;
 64     }
 65     PushDown(rt, r - l + 1);
 66     int m = (l + r) >> 1;
 67     if (p <= m) {
 68         UpdateAdd(p, add, lson);
 69     }
 70     else {
 71         UpdateAdd(p, add, rson);
 72     }
 73
 74     PushUp(rt);
 75 }
 76
 77 void UpdateModify(int p, int newVal, int l, int r, int rt)
 78 {
 79     if (l == r) {
 80         node[rt].Max = newVal;
 81         return ;
 82     }
 83     PushDown(rt, r - l + 1);
 84     int m = (l + r) >> 1;
 85     if (p <= m) {
 86         UpdateModify(p, newVal, lson);
 87     }
 88     else {
 89         UpdateModify(p, newVal, rson);
 90     }
 91
 92     PushUp(rt);
 93 }
 94
 95 void UpdateAdd_Seg(int L, int R, int add, int l, int r, int rt)
 96 {
 97     if (L <= l && r <= R) {
 98         node[rt].Max += add;
 99
100         node[rt].add += add;
101         return ;
102     }
103
104     PushDown(rt, r - l + 1);
105     int m = (l + r) >> 1;
106     if (L <= m) {
107         UpdateAdd_Seg(L, R, add, lson);
108     }
109     if (R > m) {
110         UpdateAdd_Seg(L, R, add, rson);
111     }
112
113     PushUp(rt);
114 }
115
116 void UpdateModify_Seg(int L, int R, int newVal, int l, int r, int rt)
117 {
118     if (L <= l && r <= R) {
119         node[rt].Max = newVal;
120
121         node[rt].same = true;
122         node[rt].sameVal = newVal;
123         return ;
124     }
125
126     PushDown(rt, r - l + 1);
127     int m = (l + r) >> 1;
128     if (L <= m) {
129         UpdateModify_Seg(L, R, newVal, lson);
130     }
131     if (R > m) {
132         UpdateModify_Seg(L, R, newVal, rson);
133     }
134
135     PushUp(rt);
136 }
137
138
139 int Query(int L, int R, int l, int r, int rt)
140 {
141     if (L <= l && r <= R) {
142         return node[rt].Max;
143     }
144     PushDown(rt, r - l + 1);
145     int m = (l + r) >> 1;
146     int ans = -INF;
147     if (L <= m) {
148         ans = max(ans, Query(L, R, lson));
149     }
150     if (R > m) {
151         ans = max(ans, Query(L, R, rson));
152     }
153     return ans;
154 }
155
156 int n, m;
157 int POS, ADD, NewVal, L, R;
158
159 int main()
160 {
161     int t, T, K, Q;
162     scanf("%d", &T);
163     for (t = 1; t <= T; ++t) {
164         Build(1, 1000000, 1);
165         scanf("%d%d", &K, &Q);
166         int index = 0;
167         printf("Case %d:\n", t);
168         while (Q--) {
169             ++index;
170             scanf("%d%d", &L, &R);
171             if(Query(L, R - 1, 1, 1000000, 1) < K) {
172                 printf("%d ", index);
173                 UpdateAdd_Seg(L, R - 1, 1, 1, 1000000, 1);
174             }
175         }
176         printf("\n\n");
177     }
178 }