hdu 1890 splay区间翻转

链接 ： http://acm.hdu.edu.cn/showproblem.php?pid=1890

下传翻转标记的时候要特别注意

每次将第i个数到第i大的数之间的数翻转，然后删除第i大的数

/*区间翻转，注意标记的下传*/#include<cstdio>#include<cstring>#include<algorithm>using namespace std;#define L ch[x][0]#define R ch[x][1]#define KT (ch[ ch[rt][1] ][0])const int maxn = 100010;int cmp(pair<int,int> a,pair<int,int> b){if(a.first!=b.first) return a.first<b.first;return a.second < b.second;}struct SplayTree {int sz[maxn];int ch[maxn][2];int pre[maxn];int rt,top;inline void down(int x){    if(flip[x]) {flip[ L ] ^= 1;flip[ R ] ^= 1;swap(L,R);flip[x]=0;}}inline void up(int x){sz[x]=1+sz[ L ] + sz[ R ];}inline void Rotate(int x,int f){int y=pre[x];down(y);down(x);ch[y][!f] = ch[x][f];pre[ ch[x][f] ] = y;pre[x] = pre[y];if(pre[x]) ch[ pre[y] ][ ch[pre[y]][1] == y ] =x;ch[x][f] = y;pre[y] = x;up(y);}inline void Splay(int x,int goal){//将x旋转到goal的下面down(x);//防止pre[x]就是目标点，下面的循环就进不去了，x的信息就传不下去了while(pre[x] != goal){down(pre[pre[x]]); down(pre[x]);down(x);//在旋转之前需要先下传标记，因为节点的位置可能会发生改变if(pre[pre[x]] == goal) Rotate(x , ch[pre[x]][0] == x);else   {int y=pre[x],z=pre[y];int f = (ch[z][0]==y);if(ch[y][f] == x) Rotate(x,!f),Rotate(x,f);else Rotate(y,f),Rotate(x,f);}}up(x);if(goal==0) rt=x;}inline void RTO(int k,int goal){//将第k位数旋转到goal的下面int x=rt;down(x);while(sz[ L ]+1 != k) {if(k < sz[ L ] + 1 ) x=L;else {k-=(sz[ L ]+1);x = R;}down(x);}Splay(x,goal);}void vist(int x){if(x){printf("结点%2d : 左儿子  %2d   右儿子  %2d   %2d  flip:%d\n",x,L,R,val[x],flip[x]);vist(L);vist(R);}}void Newnode(int &x,int c,int f){x=++top;flip[x]=0;L = R = 0;  pre[x] = f;sz[x]=1; val[x]=c;}inline void build(int &x,int l,int r,int f){if(l>r) return ;int m=l+r>>1;Newnode(x,num[id[m]].first,f);mp[id[m]]=x;build(L , l , m-1 , x);build(R , m+1 , r , x);pre[x]=f;up(x);}inline void init(int n){ch[0][0]=ch[0][1]=pre[0]=sz[0]=0;rt=top=0; flip[0]=0; val[0]=0;for(int i=1;i<=n;i++)   {scanf("%d",&num[i].first);num[i].second=i;}sort(num+1,num+n+1,cmp);for(int i=1;i<=n;i++)   id[num[i].second] = i;build(rt,1,n,0);}void Del(){     int t=rt; if(ch[rt][1]) { rt=ch[rt][1]; RTO(1,0); ch[rt][0]=ch[t][0]; if(ch[rt][0]) pre[ch[rt][0]]=rt; } else rt=ch[rt][0]; pre[rt]=0; up(rt);}void solve(int n){for(int i=1;i<=n;i++) {Splay(mp[i],0);printf("%d",i+sz[ ch[rt][0] ]);flip[ch[rt][0]]^=1;Del();            printf(i==n ? "\n": " ");}     }pair<int,int> num[maxn];int id[maxn];int mp[maxn];int flip[maxn];int val[maxn];}spt;int main(){int n;while(scanf("%d",&n),n){spt.init(n);spt.solve(n);}return 0;}