PAT 1138 Postorder Traversal
Suppose that all the keys in a binary tree are distinct positive integers. Given the preorder and inorder traversal sequences,you are supposed to output the first number of the postorder traversal sequence of the corresponding binary tree. Input Specification: Output Specification: Sample Input:
Sample Output:
#include<iostream> //海星 #include<vector> using namespace std; vector<int> pre,in; int flag=0; void solve(int lb,int le,int rb,int re){ if(lb>le) return ; if(lb==le&&flag++==0) cout<<pre[lb]<<endl; int i=rb; while(i<=re&&in[i]!=pre[lb]) i++; solve(lb+1,lb+i-rb,rb,i-1); solve(lb+i-rb+1,le,i+1,re); } int main(){ int n; cin>>n; pre.resize(n),in.resize(n); for(int i=0; i<n; i++) cin>>pre[i]; for(int i=0; i<n; i++) cin>>in[i]; solve(0,n-1,n-1); return 0; } (编辑:李大同) 【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容! |