Binary tree (8)----The first binary tree K-layer node and the binary part K-leaf node layer, recursive and non-recursive

1. Binary definition

typedef struct BTREENODEELEMENT_T_ {    void *data;} btreenodeelement_t;typedef struct Btreenode_t_ {    btreenodeelement_t *m_pelemt;    struct Btreenode_t_    *m_pleft;    struct btreenode_t_    *m_pright;} btreenode_t;

2. Find the number of nodes in the K-layer of the binary tree

(1) Recursive mode:

Given root node Proot:

Suppose proot is empty, or the number of layers Kthlevel <= 0. is either an empty tree or a non-requirement. then returns 0;

Assuming that the proot is not empty and the layer kthlevel==1 at this point, then Proot is one of the K-tier nodes, then 1 is returned;

Assume that the proot is not empty. And at this time the number of layers Kthlevel > 1. Then the number of Proot Zuozi (KTHLEVEL-1) layer nodes and the Proot right subtree (KthLevel-1) layer nodes must be required at this time.

int  getbtreekthlevelnodestotal (btreenode_t *proot, int kthlevel) {    if (proot = = NULL | | Kthlevel <= 0)        return 0;    if (proot! = NULL && Kthlevel = = 1)        return 1;    Return (Getbtreekthlevelnodestotal (Proot->m_pleft, KTHLEVEL-1) + getbtreekthlevelnodestotal (Proot->m_pright, KTHLEVEL-1));}

(2) Non-recursive mode

With queue implementations:

int Getkthlevelnodestotal (btreenode_t *proot, unsigned int kthlevel) {    if (proot = = NULL)        return 0;    Queue <btreenode_t *>  que;    Que.push (proot);    int curlevelnodestotal = 0;    int curlevel = 0;       while (!que.empty ()) {        ++curlevel;//current number of layers        curlevelnodestotal = Que.size ();        if (Curlevel = = kthlevel)//Assume that the number of layers equals the given number of layers break            ;        int cntnode = 0;        while (Cntnode < curlevelnodestotal) {//The next layer node is enqueued            ++cntnode;            Proot = Que.front ();            Que.pop ();            if (proot->m_pleft! = NULL)                que.push (proot->m_pleft);            if (proot->m_pright! = NULL)                que.push (proot->m_pright);}    }        while (!que.empty ())        que.pop ();    if (Curlevel = = kthlevel)        return curlevelnodestotal;    return 0;  Suppose Kthlevel is greater than the depth of the tree}

3, find the binary tree K-Layer leaf node points

(1) Recursive method

Given node Proot:

If the proot is empty, or if the number of layers Kthlevel <= 0, the empty tree or the layer number is illegal, then 0 is returned;

Suppose Proot is not empty, and when the layer is kthlevel==1, it is necessary to infer whether it is a leaf node:

Assuming that all proot are empty, then Proot is one of the leaf nodes of the K-layer. then returns 1;

Assuming that one of the proot trees is present, the proot is not a leaf node. then returns 0;

Assuming that proot is not empty, and at this point the layer kthlevel > 1, it is necessary to return the Saozi right subtree node of the KTHLEVEL-1 layer.

int Getbtreekthlevelleafnodestotal (btreenode_t *proot, int kthlevel) {    if (proot = = NULL | | Kthlevel <= 0)        return 0;    if (proot! = null && Kthlevel = = 1) {        if (Proot->m_pleft = = NULL && Proot->m_pright = = null) 
   return 1;        else            return 0;    }    Return (Getbtreekthlevelleafnodestotal (  proot->m_pleft,  KthLevel-1) + getbtreekthlevelleafnodestotal ( Proot->m_pright, KthLevel-1));}

(2) Non-recursive mode

With queue implementation

int Getkthlevelnodestotal (btreenode_t *proot, unsigned int kthlevel) {if (Proot = = NULL) return 0;    Queue <btreenode_t *> que;    Que.push (Proot);    int curlevelnodestotal = 0;       int curlevel = 0;        while (!que.empty ()) {++curlevel;//Current number of layers Curlevelnodestotal = Que.size ();        if (Curlevel = = kthlevel)//Assume that the number of layers equals the given number of layers break;        int cntnode = 0;            while (Cntnode < curlevelnodestotal) {//The next layer node is enqueued ++cntnode;            Proot = Que.front ();            Que.pop ();            if (proot->m_pleft! = NULL) Que.push (proot->m_pleft);        if (proot->m_pright! = NULL) Que.push (proot->m_pright);        }} if (curlevel = = kthlevel) {int cntnode = 0;        int leafnodes = 0;                while (Cntnode < curlevelnodestotal) {++cntnode;                Proot = Que.front ();                               Que.pop (); if (PROOT-&GT;M_PLEFT = = NULL && Proot->m_pright = = null) leafnodes++; } return leafnodes;  Returns the number of leaf nodes} return 0; Suppose the kthlevel is greater than the depth of the tree}

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Binary tree (8)----The first binary tree K-layer node and the binary part K-leaf node layer, recursive and non-recursive