Data Structure Tutorial Lesson 35th Experiment Seven Search

Teaching Purpose: practice sequential lookup, binary lookup and binary sort tree implementation

Teaching Focus:

Teaching Difficulties:

Teaching Content:

Sequential Lookup

Binary find

Sequential lookup and Binary lookup examples

#include <stdio.h> typedef int KEYTYPE;
  typedef struct{KEYTYPE Key;
  int maths;
int 中文版;
}elemtype; #define EQ (A,b) ((a) = = (b)) #define LT (A,b) ((a) < (b)) #define LQ (A,b) ((a) <= (b)) typedef struct {Elemtype *el
  Em
int length;

}sstable;
  int Search_seq (sstable st,keytype key) {int i;
  St.elem[0].key=key; for (i=st.length;!) EQ (St.elem[i].key,key);
  I.);
return i;
  int Search_bin (sstable st,keytype key) {int low,mid,high;
  Low=1;high=st.length;
    while (Low<=high) {mid= (Low+high)/2;
    If EQ (Key,st.elem[mid].key) return mid;
    else if LT (Key,st.elem[mid].key) high=mid-1;
  else Low=mid +1;
  } getdata (Sstable * t) {FILE *FP;
  int i=1;
  Fp=fopen ("Stu.txt", "R");
  FSCANF (FP, "%d",& (t->length)); while (i<=t->length) {fscanf (FP, "%d%d%d",& (T->elem[i].key), & (T->elem[i].maths),& (t
      ->elem[i].english));
    i++;
Fclose (FP);
  Main () {elemtype stu[50]; Sstable class;
  int i,j,k;
  Long time;


  Class.elem=stu;

  GetData (&class);
  printf ("This class has%d students.\n", class.length);
  printf ("Input Stuno you want search:\n");

  scanf ("%d", &k);
  I=search_seq (CLASS,K);
  J=search_bin (CLASS,K);
  printf ("Maths english\n");
  printf ("%d%d\n", class.elem[i].maths,class.elem[i].english);

  printf ("%d%d\n", class.elem[j].maths,class.elem[j].english);
      for (i=1;i<=4;i++) {j=stu[i].maths+stu[i].english;
    printf ("%d\n", j); }

}

Two-fork Sort tree

Example

#include <alloc.h> #define ERROR 0;
#define FALSE 0;
#define TRUE 1;


#define OK 1;
typedef int ELEMTYPE;
typedef int STATUS;

typedef int KEYTYPE;
  #define EQ (A,b) ((a) = = (b)) #define LT (A,b) ((a) < (b)) #define LQ (A,b) ((a) <= (b)) typedef struct BINARYTREE {
  Elemtype data;
  struct BinaryTree *l;
struct BinaryTree *r;

}*bitree,binode;

Binode * NEW () {return ((Binode *) malloc (sizeof (Binode)));} Createsubtree (bitree *t,elemtype *all,int i) {if (all[i]==0) | |
      I&GT;16) {*t=null;
    return OK;
  } *t=new ();
  if (*t==null) return ERROR;
  (*t)->data=all[i];
  Createsubtree (& (*t)->l), all,2*i);
Createsubtree (& (*t)->r), all,2*i+1);
  } createbitree (Bitree *t) {elemtype all[16]={0,1,2,3,0,0,4,5,0,0,0,0,6,0,0,0,};
Createsubtree (t,all,1);

} printelem (Elemtype d) {printf ("%d\n", d);} Preordertraverse (Bitree t,int (*visit) (Elemtype D)) {if (T) {if (Visit (T->data)) if (preordertraverse , Visit)) if (PreordErtraverse (t->r,visit)) return OK;
  return ERROR;
else return OK; } inordertraverse (Bitree t,int (*visit) (Elemtype D)) {if (T) {if (Inordertraverse (t->l,visit)) if (Visit
    Gt;data)) if (Inordertraverse (t->r,visit)) return OK;
  return ERROR;
}else return OK; Status Searchbst (bitree t,keytype key,bitree f,bitree *p) {if (!)
  T) {*p=f;return FALSE;}
  else if EQ (key,t->data) {*p=t;return TRUE;}
  else if LT (key,t->data) Searchbst (t->l,key,t,p);
else Searchbst (t->r,key,t,p);
  Status Insertbst (Bitree *t,elemtype e) {Bitree p;
  Bitree s; if (!
    Searchbst (*t,e,null,&p)) {s= (bitree) malloc (sizeof (Binode));
    s->data=e;s->l=s->r=null;
    if (!p) *t=s;
    else if (LT (e,p->data)) p->l=s;
    else p->r=s;
  return TRUE;
else return FALSE;
  } void Delete (Bitree *p) {Bitree q,s; if (!) (
    *P)->r) {q= (*p);
    (*p) = (*p)->l;
  Free (q); Or else if (!
    *P)->l) {q= (*p); (*p) = (*p)->r;
    Free (q);
    else {/* q= (*P);
    S= (*p)->l;
    while (s->r) {q=s; S=s->r}
    (*p)->data=s->data;
    if (q!= (*p)) q->r=s->l;
    else q->l=s->l;
    Free (s);
    * * q=s= (*P)->l;
    while (S->r) s=s->r;
    S->r= (*p)->r;
    Free (*p);

  (*p) =q; } Status Deletebst (Bitree *t,keytype key) {if (!) (
  *t)) {return FALSE;}
    else{if (EQ (key, (*t)->data) Delete (T);
    else if (LT (key, (*t)->data) Deletebst ((*t)->l), key);
    Else Deletebst (& ((*t)->r), key);
  return TRUE;
  } main () {Bitree root;
  Bitree Sroot=null;
  int i;
  int a[10]={45,23,12,3,33, 27,56,90,120,62};
  System ("CLS");
  Createbitree (&root);
  printf ("preordertraverse:\n");
  Preordertraverse (Root,printelem);
  printf ("inordertraverse:\n");
  Inordertraverse (Root,printelem);
  for (i=0;i<10;i++) Insertbst (&sroot,a[i]);
  printf ("inordertraverse:\n");
  Inordertraverse (Sroot,printelem); for (I=0;I&Lt;3;i++) Deletebst (&sroot,a[i]);
  printf ("Now Sroot has nodes:\n");
Inordertraverse (Sroot,printelem); }