生成二叉数及二叉树的遍历

生成二叉数及二叉树的遍历

中序生成满二叉数

linkedQueue<binaryTreeNode<char> *> q;
void insertByLevel(char a, int j, int l) {
     
    if (!q.empty()&&j<l) {
     
        binaryTreeNode<char> *t = q.front();
        q.pop();
        t->element = a;
        if (2 * j + 1 < l) {
     
            t->leftChild = new binaryTreeNode<char>;
            q.push(t->leftChild);
        }
        else {
     
            t->leftChild = NULL;
        }
        if (2 * j + 2 < l) {
     
            t->rightChild = new binaryTreeNode<char>;
            q.push(t->rightChild);
        }
        else {
     
            t->rightChild = NULL;
        }
    }
}

binaryTreeNode<char> *creatByLevel(string str) {
     
    int length = (int) str.size();
    while (!q.empty()) {
     
        q.pop();
    }
    auto *t = new binaryTreeNode<char>;
    q.push(t);
    for (int j = 0; j < length; ++j) {
     
        insertByLevel(str.at(j), j, length);
    }
    return t;
}

根据前序和中序生成二叉树

binaryTreeNode<char> *creatByPreAndIn(string str1, string str2) {
     
    int l = (int) str1.size();
    auto *t = new binaryTreeNode<char>;
    t->element = str1.at(0);
    for (int i = 0; i < l; ++i) {
     
        if (str2.at(i) == str1.at(0)) {
     
            if (i != 0&&l>1) {
     
                t->leftChild = creatByPreAndIn(str1.substr(1, i), str2.substr(0, i));
            } else {
     
                t->leftChild = NULL;
            }
            if (l > i + 1) {
     
                t->rightChild = creatByPreAndIn(str1.substr(i + 1, l - i - 1), str2.substr(i + 1, l - i - 1));
            } else {
     
                t->rightChild = NULL;
            }
        }
    }
    return t;
}

二叉树的遍历

//输出
template<class T>
void visit(binaryTreeNode<T> *x, const int *i, int l) {
     
        if (x!= nullptr) {
     
            if (i[0] < l - 1) {
     
                cout << x->element << ",";
            } else if (i[0] == l - 1) {
     
                cout << x->element << endl;
            }
        }
}

//前序遍历
template<class T>
void preOrder(binaryTreeNode<T> *t, int *i, int l) {
     
    if (t != NULL) {
     
        visit(t, i, l);
        i[0]++;
        preOrder(t->leftChild, i, l);
        preOrder(t->rightChild, i, l);
    } else{
     
        return;
    }
}
//中序遍历
template<class T>
void inOrder(binaryTreeNode<T> *t, int *i, int l) {
     
    if (t != NULL) {
     
        inOrder(t->leftChild, i, l);
        visit(t, i, l);
        i[0]++;
        inOrder(t->rightChild, i, l);
    } else{
     
        return;
    }
}
//后序遍历
template<class T>
void postOrder(binaryTreeNode<T> *t, int *i, int l) {
     
    if (t != NULL) {
     
        postOrder(t->leftChild, i, l);
        postOrder(t->rightChild, i, l);
        visit(t, i, l);
        i[0]++;
    } else{
     
        return;
    }
}