树子系统实现二叉树的创建，先序遍历，中序遍历，后序遍历，求叶子数，求结点数，求树的深度

/*二叉树子系统的实现*/ #include<stdio.h> #include<stdlib.h> #define MAXLEN 100 typedef struct BT { char data; struct BT *Lchild; struct BT *Rchild; }BT; int count = 0; BT *Create_BT() /*创建二叉树*/ { BT *T; char x; scanf("%c",&x); //getchar(); if(' '==x) T = NULL; else { T=(BT*)malloc(sizeof(BT)); T->data = x; printf("\n\t\tLchild Node:",T->data); T->Lchild = Create_BT(); printf("\n\t\tRchild Node:",T->data); T->Rchild = Create_BT(); } return T; } void PreOrder (BT *T) /*DLR*/ { if(T) { printf("%3c",T->data); PreOrder(T->Lchild); PreOrder(T->Rchild); } } void InOrder (BT *T) /*LDR*/ { if(T) { InOrder(T->Lchild); printf("%3c",T->data); InOrder(T->Rchild); } } void PostOrder (BT *T) /*LRD*/ { if(T) { PostOrder(T->Lchild); PostOrder(T->Rchild); printf("%3c",T->data); } } void LevelOrder (BT *T) { int i,j; BT *q[100],*p; p=T; if(p!=NULL) { i=1;q[i]=p;j=2;} while(i!=j) { p=q[i];printf("%3c",p->data); if(p->Lchild!=NULL) { q[j]=p->Lchild;j++; } if(p->Rchild!=NULL) { q[j]=p->Rchild;j++; } i++; } } void LeafNum (BT *T) { if(T) { if(T->Lchild==NULL&&T->Rchild==NULL) count++; LeafNum(T->Lchild); LeafNum(T->Rchild); } } void NodeNum (BT *T) { if(T) { count++; NodeNum(T->Lchild); NodeNum(T->Rchild); } } int TreeDepth (BT *T) { int ldep,rdep; if(T==NULL) return 0; else { ldep=TreeDepth(T->Lchild); rdep=TreeDepth(T->Rchild); if(ldep>rdep) return ldep+1; else return rdep+1; } } void ShowTree (BT *T) { BT *stack[MAXLEN],*p; int level[MAXLEN][2],top,n,i,width=4; if(T) { printf("\n\t\tShowTree:\n\t\t"); top=1; stack[top]=T; level[top][0]=width; while(top>0) { p=stack[top]; n=level[top][0]; for(i=1;i<=n;i++) printf(" "); printf("%c",p->data); for(i=n+1;i<50;i+=2) printf(" "); top--; if(p->Rchild!=NULL) { top++; stack[top]=p->Rchild; level[top][0]=n+width; level[top][1]=2; } if(p->Lchild!=NULL) { top++; stack[top]=p->Lchild; level[top][0]=n+width; level[top][1]=1; } } } } void main() /*主函数*/ { BT *T=NULL; char ch1,ch2,a; ch1='y'; while(ch1=='y'||ch1=='Y') { printf("\n\n\n\n"); printf("\n\t\t\tBT System"); printf("\n\t\t**************************"); printf("\n\t\t 1.Creater a BT"); printf("\n\t\t 2.ShowTree"); printf("\n\t\t 3.PreOrder"); printf("\n\t\t 4.InOrder"); printf("\n\t\t 5.PostOrder"); printf("\n\t\t 6.LevelOrder"); printf("\n\t\t 7.LeafNum"); printf("\n\t\t 8.NodeNum"); printf("\n\t\t 9.TreeDepth"); printf("\n\t\t 0.Exit"); printf("\n\t\t**************************"); printf("\n\t\t Please Select A Num(0~9):"); scanf("%c",&ch2); getchar(); printf("\n"); switch(ch2) { case '1': printf("\n\t\tInput BT Node By PreOrder:" ); printf("\n\t\tInput root Node:"); T=Create_BT(); printf("\n\t\tCreate BT successfully!"); break; case '2': ShowTree(T);break; case '3': printf("\n\t\tDLR: "); PreOrder(T); break; case '4': printf("\n\t\tLDR:"); InOrder(T); break; case '5': printf("\n\t\tLRD:"); PostOrder(T); break; case '6': printf("\n\t\tLevel:"); LevelOrder(T); break; case '7': count=0; LeafNum(T); printf("\n\t\tThe BT have %d Leaf.\n",count); break; case '8': count=0; NodeNum(T); printf("\n\t\tThe BT have %d Node.\n",count); break; case '9': printf("\n\t\tThe TreeDepth is %d.\n",TreeDepth(T)); break; case '0': ch1='n'; break; default: printf("\n\t\t******Input Wrong !"); } if(ch2!='0') { printf("\n\t\tPress Enter countinue Or press any key Exit\n"); a=getchar(); if(a!='\xA') { getchar();ch1='n'; } } } }