trees.c

#include <stdio.h>
#include <stdlib.h>
#include <conio.h>
typedef struct Node{
	int key;
	struct Node *left;
	struct Node *right;
} Node;
typedef Node *PNode;
PNode Root=NULL;

PNode CreateNode (int ke){
	PNode NewNode=(PNode)malloc(sizeof(Node));
	NewNode->key=ke;
	NewNode->left=NULL;
	NewNode->right=NULL;
	return NewNode;
}

void Insert(PNode New, PNode Base) {
	if (Base == NULL) {
		Base = New;
	}
	if (New->key > Base->key)
		if (Base->right == NULL)Base->right = New;
		else Insert(New, Base->right);
	else if (New->key < Base->key)
		if (Base->left == NULL)Base->left = New;
		else Insert(New, Base->left);
	else Base->key = New->key;
}

void input(){
	PNode NewNode;
	int a;
	char ch;
	do{
		puts ("vvedite kluch");
		scanf("%d", &a);
		if(Root == NULL) {
			Root = CreateNode(a);
		}
		else {
			Insert(CreateNode(a), Root);
		}
		puts("esche?");
		ch=getch();
		}
while(ch !='n');
return;
}

void printklp(PNode from){
	if (from!=NULL){
		printf("%5d \n",from->key);
		printklp(from->left);
		printklp(from->right);
	}
}

void printlkp(PNode from){
	if (from!=NULL){
		printlkp(from->left);
		printf("%5d \n",from->key);
		printlkp(from->right);
	}
}

void printlpk(PNode from){
	if (from!=NULL){
		printlpk(from->left);
		printlpk(from->right);
		printf("%5d \n",from->key);
	}
}

void add(){
	PNode NewNode;
	int a;
	puts ("vvedite kluch");
	scanf("%d \n", &a);
	Insert(CreateNode(a), Root);
}

int leafsOnLevel (int i, PNode startFrom) {
	if (i != 0) {
		return (leafsOnLevel(i-1, startFrom->left) + leafsOnLevel(i-1, startFrom->right));
	}
	if (startFrom == NULL) {
		puts("ERROR!");
		return 0;
	}
	if(startFrom->left || startFrom->right) {
		return 0;
	}
	return 1;
}

int nodesOnTree(PNode startFrom) {
	int i;
	if(startFrom == NULL) {
		return 0;
	}
	i = 1 + nodesOnTree(startFrom->left) + nodesOnTree(startFrom->right);
}



int main(){
char c;
int a;
	while (1){//clrscr();
	  puts("a-create a new binary tree");
	  puts("b-straight traversal");
	  puts("c-symmetrical traversal");
	  puts("d-reverse traversal");
	  puts("e-adding element");
	  puts("1-count leafs on level");
	  puts("2-count nodes on whole tree without leafs");
	  puts("0-exit");
	  c=getch();
	  switch(c) {
		  case 'a':input(); break;
		  case 'b':printklp(Root); break;
		  case 'c':printlkp(Root); break;
		  case 'd':printlpk(Root); break;
		  case 'e':add(); break;
		  case '1':
					    puts ("vvedite uroven");
							scanf("%d", &a);
							printf("%d\n", leafsOnLevel(a, Root)); break;
	  	case '2':
							printf("%d\n", nodesOnTree(Root)); break;
		  case '0': return 0;
	  	defaults: puts("Wrong mode");
		}
	}
}