Uva548 tree

Enter the middle order and post order traversal of a binary tree , Please output a leaf node , The sum of values from the leaf node to the root is the smallest , And this leaf is the one with the smallest number . Input ： Your program will read two lines from the input file ( Until the end of the document ). The first line is the middle order traversal value sequence of the tree , The second line is the sequence of traversal values after the tree . All values will be different , Greater than zero and less than or equal to 10000. A section of a binary tree 1<=N<=10000. Output ： For each tree description , You should output the value of the leaf node of the minimum path . In the case of minimum multipath , You should select the path with the minimum value on the terminal leaf node , And output the terminal leaf of the minimum value .

#include<bits/stdc++.h>
using namespace std;
const int maxn = 10000+5;
int order[maxn],postorder[maxn],lch[maxn],rch[maxn];
int n,minv,minsum;
// Traversing sequence to establish binary tree 
int createtree(int l1, int l2, int m){
    
    if(m <= 0){
    
        return 0;
    }
    int root = postorder[l2+m-1];
    int len = 0;
    while(inorder[l1+len] != root)// Calculate the length of the left subtree 
        len++;
    lch[root] = createtree(l1,l2,len);
    rch[root] = createtree(l1+len+1,l2+len,m-len-1);
    return root;
}

bool readline(int *a){
    // Read the traversal sequence , There's a space in the middle 
    string line;
    if(!getline(cin,line))
        return false;
    stringstream s(line);
    n = 0;
    int x;
    while(s>>x){
    
        a[n++] = x;
    return n > 0;
}
}

void findmin(int v,int sum){
    
    sum += v;
    if(!lch[v] && !rch[v])// leaf 
        if(sum < minsum || (sum == minsum&& v<minv)){
    
            minv = v;
            minsum = sum;
        }
    if(lch[v]) //v There's a Zuozi tree 
        findmin(lch[v],m);
    if(rch[v])
        findmin(rch[v],m);
}


int main(){
    
    while(readline(inorder)){
    
        readline(postorder);
        createtree(0,0,n);
        
        minsum = 0x7fffffff;
        findmin(postorder[n-1],0);
        cout<<minv<<endl;
    }
    return 0;
}