[各种面试题] 二叉树旋转查询

题目描述

http://ac.jobdu.com/problem.php?pid=1541

直接模拟就好了，但是我的代码后面的样例要超时。。。不知道为什么，把cin , cout 改成 scanf 之后居然就变成 output limit exceed 了，奇怪。

算了，思路对的就行，懒得去搞了。

#include<iostream>#include<cstdio>#include<vector>#include<string>#include<cstring>#include<climits>#include<queue>#include<map>#include<algorithm>using namespace std;struct node{int parent,left,right;int id,childsum;node():parent(-1),left(-1),right(-1),childsum(1){}};node tree[1005];int calChildSum(int rt){if(rt==-1||tree[rt].childsum!=-1)return 0;int l=calChildSum(tree[rt].left);int r=calChildSum(tree[rt].right);tree[rt].childsum=l+r+1;return tree[rt].childsum;}int children(int rt){if(rt==-1)return 0;return tree[rt].childsum;}void push_up(int rt){if(rt==-1)return;tree[rt].childsum=1+children(tree[rt].left)+children(tree[rt].right);}void rotate(int rt){if(rt==-1||tree[rt].parent==-1)return;int p=tree[rt].parent;if ( rt==tree[p].left){int r=tree[rt].right;tree[p].left=r;if(r!=-1)tree[r].parent=p;tree[rt].right=p;}else{int l=tree[rt].left;tree[p].right=l;if(l!=-1)tree[l].parent=p;tree[rt].left=p;}int pp=tree[p].parent;tree[p].parent=rt;tree[rt].parent=pp;if(pp!=-1&&tree[pp].left==p)tree[pp].left=rt;else if (pp!=-1&&tree[pp].right==p)tree[pp].right=rt;push_up(p);push_up(rt);}int main(){int n;while(cin>>n){for(int i=1;i<=n;i++){tree[i].id=i;tree[i].left=tree[i].right=-1;tree[i].parent=-1;tree[i].childsum=-1;}for(int i=1;i<=n;i++){tree[i].id=i;cin>>tree[i].left>>tree[i].right;if(tree[i].left!=-1)tree[tree[i].left].parent=i;if(tree[i].right!=-1)tree[tree[i].right].parent=i;}for(int i=1;i<=n;i++)calChildSum(i);int t;cin>>t;while(t--){string op;int id;cin>>op>>id;if(op=="size")cout<<tree[id].childsum<<endl;else if (op=="rotate")rotate(id);else if (op=="parent")cout<<tree[id].parent<<endl;}}}