二叉树子系统实现顺序查找，折中查找程序

#include<stdio.h> #include<string.h> #define MAXLEN 100 #define N 10 void seqsearch() { int a[N],i,x,y; char ch; printf("\n\t\t建立一个整数的顺序表（输入-1结束）:\n"); for(i=0;i<MAXLEN;i++) { printf("\t\t"); scanf("%d",&a[i]); getchar(); if(a[i]==-1) { y=i; break; } } printf("\n\t\t需要查找请输入Y/N？"); scanf("%c",&ch);/*getchar();*/ while(ch=='y'||ch=='Y') { printf("\n\t\t请输入要查找的数据\n\t\t"); scanf("%d",&x);getchar(); i=y-1; while(i>=0&&a[i]!=x) i--; if(i==-1) printf("\t\t没有找到\n"); else printf("\t\t已找到，在第%d的位置上\n",i+1); printf("\t\t继续查找输入Y,否则输入N:\n\t\t"); scanf("%c",&ch); } } void binsearch() { int R[MAXLEN],i,k,low,mid,high,m,nn; char ch; printf("\t\t建立递增有序的查找顺序表：\n"); for(i=0;i<MAXLEN;i++) { printf("\t\t"); scanf("%d",&R[i]); getchar(); if(R[i]==-1) { nn=i;break; } } printf("\n\t\t查找请输入Y，退出输入N：\n\t\t"); scanf("%c",&ch);getchar(); while(ch=='y'||ch=='Y') { printf("\n\t\t请输入要查找的数据：\n\t\t"); scanf("%d",&k);getchar(); low=0;high=nn-1;m=0; while(low<=high) { mid=(low+high)/2; m++; if(R[mid]>k) high=mid-1; else if(R[mid]<k) low=mid+1; else break; } if(low>high) { printf("\t\t没有找到\n"); printf("\t\t共进行%d次比较。\n",m); if(R[mid]<k) mid++; printf("\t\t可将此数插入到%d的位置上。\n",mid+1); } else { printf("\t\t要找的数据%d在第%d的位置上。\n",k,mid+1); printf("\t\t共进行%d次比较。\n",m); } printf("\t\t继续查找输入Y,否则输入N:\n\t\t"); scanf("%c",&ch);getchar(); } } void main() { int choice; char ch; ch='y'; while(ch=='y'||ch=='Y') { printf("\n\n\n\n"); printf("\t\t\t查找子系统"); printf("\n\t\t**********************************"); printf("\n\t\t 1--顺序查找"); printf("\n\t\t 2--折半查找"); printf("\n\t\t 0--返回"); printf("\n\t\t**********************************"); printf("\n\t\t请选择菜单（0--3）:"); scanf("%d",&choice); switch(choice) { case 1: seqsearch(); break; case 2: binsearch(); break; case 0: ch='n'; break; default:printf("\n\t\t菜单选择错误！请重新输入："); } } }