haxi.rar_C语言 哈希表_哈希表

#include <stdio.h> #include <string.h> #include <stdlib.h> void creathash(char hash[][20],int n); unsigned long int mid(unsigned long int s); void search(char hash[][20],char name[]); /*主函数*/ void main() { char name[20],hashlist[50][20]; int c; do{printf("\n\n 主菜单\n "); printf("\n 1.创建哈希表\n "); printf("\n 2.查找哈希表中指定的人\n "); printf("\n 3.退出程序 \n "); printf("\n 请输入你的选择:"); scanf("%d",&c); switch(c) {case 1:{creathash(hashlist,30);}break; case 2:{printf("\n please input your search name:");scanf("%c",name);gets(name);search(hashlist,name);}break; case 3:exit(0); } }while(c<=3); } /*建哈希表*/ void creathash(char hash[][20],int n) {int i,j; unsigned long int s,l; char name[20]; for(i=0;i<50;i++) strcpy(hash[i],"null"); /*哈希表初值:null*/ for(i=0;i<n;i++) { printf("input the name:\n"); gets(name); s=0;j=0; while(name[j]!='\0') s+=name[j++]; l=mid(s)%47; /*除留余数法定位*/ if(strcmp(hash[l],"null")==0) strcpy(hash[l],name); else{ do{l=(l+17)%47; /*补偿性线性探测*/ }while(strcmp(hash[l],"null")!=0); strcpy(hash[l],name); } } } /*mid函数先把参数平方，然后取中间的第4、5位作为地址返回*/ unsigned long int mid(unsigned long int s) { int i=0,a[10]; unsigned long int d=1,s0; s0=s*s; while(s0>d) d*=10; d/=10; while(d!=0){ a[i++]=s0/d; /*分离出s0的各位放在数组a中*/ s0=s0%d; d=d/10; } return(a[3]*10+a[4]); /*取中间第4、5位返回*/ } /*在哈希表中查找指定的人*/ void search(char hash[][20],char name[]) { unsigned long s=0,l; int i=0; while(name[i]!='\0') s+=name[i++]; l=mid(s)%47; if(strcmp(hash[l],name)==0) { printf("found!at %d\n",l); return; } while((strcmp(hash[l],name)!=0)&&(strcmp(hash[l],"null")!=0)) l=(l+17)%47; /*探测*/ if(strcmp(hash[l],name)==0) printf("found!at %d\n",l); else printf("no found!\n"); }