剑指offer——面试题32.1：分行从上到下打印二叉树

void BFSLayer(BinaryTreeNode* pRoot)
{
    if(pRoot==nullptr)
        return;
    queue<BinaryTreeNode*> pNode;
    int curLayer=1,nextLayer=0;
    pNode.push(pRoot);
    while(!pNode.empty())
    {
        BinaryTreeNode* pFront=pNode.front();
        cout<<pFront->m_Value<<' ';
        pNode.pop();
        curLayer--;
        if(pFront->m_pLeft!=nullptr)
        {
            nextLayer++;
            pNode.push(pFront->m_pLeft);
        }
        if(pFront->m_pRight!=nullptr)
        {
            nextLayer++;
            pNode.push(pFront->m_pRight);
        }
        if(curLayer==0)
        {
            curLayer=nextLayer;
            nextLayer=0;
            cout<<endl;
        }
    }
}

函数

  1 #include"BinaryTree.h"
  2 
  3 // ====================测试代码====================
  4 //            8
  5 //        6      10
  6 //       5 7    9  11
  7 void Test1()
  8 {
  9     BinaryTreeNode* pNode8 = CreateBinaryTreeNode(8);
 10     BinaryTreeNode* pNode6 = CreateBinaryTreeNode(6);
 11     BinaryTreeNode* pNode10 = CreateBinaryTreeNode(10);
 12     BinaryTreeNode* pNode5 = CreateBinaryTreeNode(5);
 13     BinaryTreeNode* pNode7 = CreateBinaryTreeNode(7);
 14     BinaryTreeNode* pNode9 = CreateBinaryTreeNode(9);
 15     BinaryTreeNode* pNode11 = CreateBinaryTreeNode(11);
 16 
 17     ConnectTreeNodes(pNode8, pNode6, pNode10);
 18     ConnectTreeNodes(pNode6, pNode5, pNode7);
 19     ConnectTreeNodes(pNode10, pNode9, pNode11);
 20 
 21     printf("====Test1 Begins: ====
");
 22     printf("Expected Result is:
");
 23     printf("8 
");
 24     printf("6 10 
");
 25     printf("5 7 9 11 

");
 26 
 27     printf("Actual Result is: 
");
 28     BFSLayer(pNode8);
 29     printf("
");
 30 
 31     DestroyTree(pNode8);
 32 }
 33 
 34 //            5
 35 //          4
 36 //        3
 37 //      2
 38 void Test2()
 39 {
 40     BinaryTreeNode* pNode5 = CreateBinaryTreeNode(5);
 41     BinaryTreeNode* pNode4 = CreateBinaryTreeNode(4);
 42     BinaryTreeNode* pNode3 = CreateBinaryTreeNode(3);
 43     BinaryTreeNode* pNode2 = CreateBinaryTreeNode(2);
 44 
 45     ConnectTreeNodes(pNode5, pNode4, nullptr);
 46     ConnectTreeNodes(pNode4, pNode3, nullptr);
 47     ConnectTreeNodes(pNode3, pNode2, nullptr);
 48 
 49     printf("====Test2 Begins: ====
");
 50     printf("Expected Result is:
");
 51     printf("5 
");
 52     printf("4 
");
 53     printf("3 
");
 54     printf("2 

");
 55 
 56     printf("Actual Result is: 
");
 57     BFSLayer(pNode5);
 58     printf("
");
 59 
 60     DestroyTree(pNode5);
 61 }
 62 
 63 //        5
 64 //         4
 65 //          3
 66 //           2
 67 void Test3()
 68 {
 69     BinaryTreeNode* pNode5 = CreateBinaryTreeNode(5);
 70     BinaryTreeNode* pNode4 = CreateBinaryTreeNode(4);
 71     BinaryTreeNode* pNode3 = CreateBinaryTreeNode(3);
 72     BinaryTreeNode* pNode2 = CreateBinaryTreeNode(2);
 73 
 74     ConnectTreeNodes(pNode5, nullptr, pNode4);
 75     ConnectTreeNodes(pNode4, nullptr, pNode3);
 76     ConnectTreeNodes(pNode3, nullptr, pNode2);
 77 
 78     printf("====Test3 Begins: ====
");
 79     printf("Expected Result is:
");
 80     printf("5 
");
 81     printf("4 
");
 82     printf("3 
");
 83     printf("2 

");
 84 
 85     printf("Actual Result is: 
");
 86     BFSLayer(pNode5);
 87     printf("
");
 88 
 89     DestroyTree(pNode5);
 90 }
 91 
 92 void Test4()
 93 {
 94     BinaryTreeNode* pNode5 = CreateBinaryTreeNode(5);
 95 
 96     printf("====Test4 Begins: ====
");
 97     printf("Expected Result is:
");
 98     printf("5 

");
 99 
100     printf("Actual Result is: 
");
101     BFSLayer(pNode5);
102     printf("
");
103 
104     DestroyTree(pNode5);
105 }
106 
107 void Test5()
108 {
109     printf("====Test5 Begins: ====
");
110     printf("Expected Result is:
");
111 
112     printf("Actual Result is: 
");
113     BFSLayer(nullptr);
114     printf("
");
115 }
116 
117 //        100
118 //        /
119 //       50
120 //         
121 //         150
122 void Test6()
123 {
124     BinaryTreeNode* pNode100 = CreateBinaryTreeNode(100);
125     BinaryTreeNode* pNode50 = CreateBinaryTreeNode(50);
126     BinaryTreeNode* pNode150 = CreateBinaryTreeNode(150);
127 
128     ConnectTreeNodes(pNode100, pNode50, nullptr);
129     ConnectTreeNodes(pNode50, nullptr, pNode150);
130 
131     printf("====Test6 Begins: ====
");
132     printf("Expected Result is:
");
133     printf("100 
");
134     printf("50 
");
135     printf("150 

");
136 
137     printf("Actual Result is: 
");
138     BFSLayer(pNode100);
139     printf("
");
140 }
141 
142 int main(int argc, char* argv[])
143 {
144     Test1();
145     Test2();
146     Test3();
147     Test4();
148     Test5();
149     Test6();
150 
151     return 0;
152 }

测试代码