西北农林科技大学 c语言上机 实习7答案.docx

西北农林科技大学c语言上机实习7答案

第一篇：西北农林科技大学c语言上机实习7答案实习七答案1、电话薄管理程序设计/*exer7-1手机电话簿管理*/#include#include#includeintN=0;/*定义全局变量，代表电话簿长度*/structstud/*定义结构类型*/{charname[15];charphone_num[15];charmobile_num[15];}book[100];voidcreat();voidinsert();voidsearch();voiddelete();voidoutput();intmain(void){intk;do{printf(“0:exitn”);printf(“1:creatn”);printf(“2:searchn”);printf(“3:insertn”);printf(“4:deleten”);printf(“5:outputn”);printf(“pleaseselect:”);scanf(“%d”,&k);switch(k){case0:exit(0);case1:creat();break;case2:search();break;case3:/*定义结构数组*//*函数的原型声明*//*主函数*//*打印菜单项*//*输入选择项*//*退出函数*/insert();break;case4:delete();break;case5:output();break;/*调用子函数*/default:exit(0);}}while(1);return0;}voidcreat(void)/*生成子函数*/{charappella[15];getchar();while(1)/*输入结构数组*/{gets(appella);if(*appella=='*')break;/*输入*，则结束*/strcpy(book[N].name,appella);gets(book[N].phone_num);gets(book[N].mobile_num);N++;/*统计长度*/}}voidsearch(void)/*查找子函数*/{charappella[15];inti=0;getchar();gets(appella);while(i{i++;}if(iprintf(“%s%s%sn”，book[i].name,book[i].phone_num,book[i].mobile_num);elseprintf(“notfound”);}voidinsert(void)/*插入子函数*/{getchar();gets(book[N].name);gets(book[N].phone_num);gets(book[N].mobile_num);N++;/*长度加1*/}voiddelete(void)/*删除子函数*/{charappella[15];inti=0,j;getchar();gets(appella);while(i{i++;}if(i{for(j=i+1;j{book[j-1]=book[j];}N--;/*长度减1*/}elseprintf(“notfound”);}voidoutput(void)/*输出子函数*/{inti;for(i=0;iprintf(“%s%s%sn”，book[i].name,book[i].phone_num,book[i].mobile_num);}2、正负数判断/*exer8-1判断数是正数、负数*/#includeintmain(void){shortnum,mask,bit;mask=0x8000;/*构造掩码*/scanf(“%hx”,&num);/*输入数据*/bit=(mask&num)?1:0;/*取出第一位*/if(bit==0)printf(“ispositivenumbern”);/*输出正数*/elseprintf(“isnegativenumbern”);/*输出负数*/return0;}3、偶数位清零/*exer8-3将偶数位清零，其它位保留*/#includeintmain(void){unsignedshorta,b,mask;mask=0x5555;/*构造掩码*/scanf(“%hx”,&a);/*输入数据a*/b=a&mask;/*与掩码按位与*/printf(“%xn”,b);/*输出*/return0;}4、结构体的定义与引用#include/*定义结构体*/structemployee{charname[100];charID[20];intage;floatsalary;};intmain(){/*定义结构体变量*/structemployeestaff;/*输入数据*/ge