PAT(A)1020. Tree Traversals

include

#include 
typedef struct node{
    int data;
    struct node* left,*right;
}TreeNode,*Tree;
Tree BuiltTree(int *post,int *in,int n )//由其他两种序列建立树的过程，递归
{
    int i;
    Tree root=(Tree)malloc(sizeof(TreeNode));
    root->data=post[n-1];
    root->left=root->right=NULL;
    for(i=0;i0){
        root->left=BuiltTree(post,in,i);
    }
    if(n-i-1>0){
        root->right=BuiltTree(post+i,in+i+1,n-i-1);
    }
    return root;
}
void LevelOrder(Tree s){//层序遍历
    int isfirst=1;
    TreeNode *queue[30];
    int front=0,rear=0;
    queue[rear++]=s;
    while(front!=rear){
        TreeNode* t=queue[front++];
        if(isfirst){
            isfirst=0;
            printf("%d",t->data );
        }
        else{
            printf(" %d",t->data );
        }
        if(t->left){
            queue[rear++]=t->left;
        }
        if(t->right){
            queue[rear++]=t->right;
        }
    }
}
int main(){
//  freopen("in.txt","r",stdin);
    int n;
    int post[30],in[30];
    scanf("%d",&n);
    for(int i=0;i