M - 约会安排 HDU - 4553 线段树 （最长连续段）

Posted 2021-02-07 ttttttttrx

中文题面

思路：维和两个区间  一个是女神区间 一个是基友区间  如果是基友要预约时间 直接在基友区间查询可满足的起点 （这里先判tree[1].m >=length也就是有没有这样的区间满足时间length） 预约成功后更新基友区间

如果是女神要预约区间 先在基友区间预约看有没有满足的区间 （同样看根节点的m） 如果有 同时更新两个区间 如果没有继续在女神区间查找 如果女神区间有 则同时更新基友和女神区间 如果没有 那就真没有了直接输出 题目要求的话

  1 #include<bits/stdc++.h>
  2 using namespace std;
  3 const int maxn=1e6+5;
  4 struct Node{
  5     int l,r;
  6     int ml,mr,m;
  7 }tree1[maxn*4],tree2[maxn*4];
  8 void build(int x,int l,int r){
  9     tree1[x].l=tree2[x].l=l;
 10     tree1[x].r=tree2[x].r=r;
 11     tree1[x].ml=tree2[x].ml=tree1[x].mr=tree2[x].mr=tree1[x].m=tree2[x].m=r-l+1;
 12     if(l==r)return ;
 13     int mid=l+r>>1;
 14     build(x<<1,l,mid);
 15     build(x<<1|1,mid+1,r);
 16 }
 17 void push_up(int x){
 18     int mid=tree1[x].r+tree1[x].l>>1;
 19     tree1[x].ml=tree1[x<<1].ml;
 20     tree1[x].mr=tree1[x<<1|1].mr;
 21     tree1[x].m=max(max(tree1[x<<1].m,tree1[x<<1|1].m),tree1[x<<1].mr+tree1[x<<1|1].ml);
 22     if(tree1[x<<1].ml==mid-tree1[x].l+1)tree1[x].ml+=tree1[x<<1|1].ml;
 23     if(tree1[x<<1|1].mr==tree1[x].r-mid)tree1[x].mr+=tree1[x<<1].mr;
 24 
 25     tree2[x].ml=tree2[x<<1].ml;
 26     tree2[x].mr=tree2[x<<1|1].mr;
 27     tree2[x].m=max(max(tree2[x<<1].m,tree2[x<<1|1].m),tree2[x<<1].mr+tree2[x<<1|1].ml);
 28     if(tree2[x<<1].ml==mid-tree2[x].l+1)tree2[x].ml+=tree2[x<<1|1].ml;
 29     if(tree2[x<<1|1].mr==tree2[x].r-mid)tree2[x].mr+=tree2[x<<1].mr;
 30 
 31 }
 32 void push_down(int x){
 33     int mid=tree1[x].l+tree1[x].r>>1;
 34     if(tree1[x].m==tree1[x].r-tree1[x].l+1){
 35         tree1[x<<1].ml=tree1[x<<1].mr=tree1[x<<1].m=mid-tree1[x].l+1;
 36         tree1[x<<1|1].ml=tree1[x<<1|1].mr=tree1[x<<1|1].m=tree1[x].r-mid;
 37     }
 38     else if(tree1[x].m==0){
 39         tree1[x<<1].ml=tree1[x<<1].mr=tree1[x<<1].m=0;
 40         tree1[x<<1|1].ml=tree1[x<<1|1].mr=tree1[x<<1|1].m=0;
 41     }
 42 
 43     if(tree2[x].m==tree2[x].r-tree2[x].l+1){
 44         tree2[x<<1].ml=tree2[x<<1].mr=tree2[x<<1].m=mid-tree2[x].l+1;
 45         tree2[x<<1|1].mr=tree2[x<<1|1].ml=tree2[x<<1|1].m=tree2[x].r-mid;
 46     }
 47     else if(tree2[x].m==0){
 48             tree2[x<<1].ml=tree2[x<<1].mr=tree2[x<<1].m=0;
 49         tree2[x<<1|1].mr=tree2[x<<1|1].ml=tree2[x<<1|1].m=0;
 50     }
 51 }
 52 void update(int x,int l,int r,int value){
 53     if(tree1[x].l>=l&&tree1[x].r<=r){
 54         if(value==1){
 55             tree1[x].ml=tree1[x].mr=tree1[x].m=0;
 56         }
 57         else if(value==2){
 58             tree1[x].ml=tree1[x].mr=tree1[x].m=0;
 59             tree2[x].ml=tree2[x].mr=tree2[x].m=0;
 60         }
 61         else {
 62             tree1[x].ml=tree1[x].mr=tree1[x].m=tree1[x].r-tree1[x].l+1;
 63             tree2[x].ml=tree2[x].mr=tree2[x].m=tree1[x].r-tree1[x].l+1;
 64         }
 65         return ;
 66     }
 67     int mid=tree1[x].l+tree1[x].r>>1;
 68     push_down(x);
 69     if(mid>=l)update(x<<1,l,r,value);
 70     if(mid<r)update(x<<1|1,l,r,value);
 71     push_up(x);
 72 }
 73 int  query(int x,int length,int value){
 74     if(tree1[x].l==tree1[x].r)return tree1[x].l;
 75     push_down(x);
 76     int mid=tree1[x].l+tree1[x].r>>1;
 77     if(value==1){
 78         if(tree1[x<<1].m>=length){
 79             return query(x<<1,length,value);
 80         }
 81         else if(tree1[x<<1].mr+tree1[x<<1|1].ml>=length){
 82             return mid-tree1[x<<1].mr+1;
 83         }
 84         else return query(x<<1|1,length,value);
 85     }
 86     else {
 87             if(tree2[x<<1].m>=length){
 88             return query(x<<1,length,value);
 89         }
 90         else if(tree2[x<<1].mr+tree2[x<<1|1].ml>=length){
 91             return mid-tree2[x<<1].mr+1;
 92         }
 93         else return query(x<<1|1,length,value);
 94     }
 95 }
 96 int main(){
 97     int t;
 98     int kase=1;
 99     scanf("%d",&t);
100     char s[100];
101     int temp;
102     int q;
103     int  n;
104     while(t--){
105         printf("Case %d:
",kase++);
106         scanf("%d%d",&n,&q);
107         build(1,1,n);
108         while(q--){
109             scanf("%s%d",s,&temp);
110             if(s[0]==‘D‘){
111                 if(tree1[1].m>=temp){
112                     int start=query(1,temp,1);
113                     update(1,start,start+temp-1,1);
114                  printf("%d,let‘s fly
",start);
115                 }
116                 else printf("fly with yourself
");
117             }
118             else if(s[0]==‘N‘){
119                 if(tree1[1].m>=temp){
120                     int start=query(1,temp,1);
121                     update(1,start,start+temp-1,2);
122                  printf("%d,don‘t put my gezi
",start);
123                 }
124                 else if(tree2[1].m>=temp){
125                     int start=query(1,temp,0);
126                     update(1,start,start+temp-1,2);
127                  printf("%d,don‘t put my gezi
",start);
128                 }
129                 else   printf("wait for me
");
130             }
131             else {
132                 int zz;
133                 scanf("%d",&zz);
134                 update(1,temp,zz,3);
135                 printf("I am the hope of chinese chengxuyuan!!
");
136             }
137         }
138 
139     }
140     return 0;
141 }