求好人讲解C语言代码每一句话
#include<stdio.h>#include<string.h>
#include<math.h>
#include<stdlib.h>
struct STUDENT{
char name[10];
char number[10];
char sex;
int age;
float english,C_program;
float total,average;
};
void display()
{
printf("------------------------------------------\n");
printf(" 1.输入信息 \n");
printf(" 2.输出信息 \n");
printf(" 3.按年龄查询 \n");
printf(" 4.按性别查询 \n");
printf(" 5.按姓名查询 \n");
printf(" 6.按学号排序 \n");
printf(" 7.按总分排序 \n");
printf(" 8.查找总分最大的 \n");
printf(" 9.退出系统 \n");
printf("------------------------------------------\n");
}
void input(struct STUDENT *s,int length)
{
int i;
char sex;
// int sex_flag;
// char temp_char;
getchar();
//跨过回车符
//printf("|姓名|学号|性别|年龄|英语|C语言|总分|平均分|\n");
for(i=0;i<length;i++)
{
printf("请输入第%d个人姓名",i+1);
gets(s->name);//scanf("%s",s->name);
printf("请输入第%d个人学号",i+1);
gets(s->number);//scanf("%s",s->number);
printf("请输入第%d个人性别",i+1);
/*while(sex_flag!=1)
{
scanf("%c",&temp_char);
if((temp_char=='f' )||( temp_char=='F')||(temp_char=='m')||(temp_char=='M'))
{
s->sex=temp_char;
sex_flag=1;break;
}
else
{
printf("性别输入错误，请重新输入:");
}
}*/
do
{
sex=getchar();
while(getchar()!='\n');
if(sex!='f'&&sex!='F'&&sex!='M'&&sex!='m')
printf("请重新输入‘F’或‘M’或‘f’或‘m’！\n");
}while(sex!='F'&&sex!='f'&&sex!='M'&&sex!='m');
s->sex=sex;
printf("请输入第%d个人年龄",i+1);
scanf("%d",&s->age);
printf("请输入第%d个人的英语、C语言",i+1);
scanf("%f%f",&s->english,&s->C_program);
s->total=s->english+s->C_program;
s->average=s->total/2;
getchar();//跨过回车键
s++;//指针向后移
}
}
void output(struct STUDENT *s,int length)
{
int i;
printf("********************************************\n");
printf("|姓名|学号|性别|年龄|英语|C语言|总分|平均分|\n");
for(i=0;i<length;i++)
{
printf("%4s%4s%4c%4d%6.1f%6.1f%6.1f%7.1f\n",s->name,s->number,s->sex,s->age,s->english,s->C_program,s->total,s->average);
s++;
}
}
//年龄查询并统计多少人符合条件
void query_for_age(struct STUDENT *s,int length)
{
int age;
int i,count=0;
printf("请输入你要查询的年龄:");
scanf("%d",&age);
for(i=0;i<length;i++,s++)
{
if(s->age==age)
{
printf("%4s%2c%5.2f\n",s->name,s->sex,s->total);
count++;
}
}
if(count==0)
printf("没找到符合条件！\n");
else
printf("共找到复合条件的%d个\n",count);
}
//性别统计
void query_for_sex(struct STUDENT *s,int length)
{
int i,count_f=0,count_m=0;
int total=0;
for(i=0;i<length;i++)
{
if(s->sex=='f'||s->sex=='F')
count_f++;
else
count_m++;
s++;
}
printf("男生总数为%d,女生总数为%d\n",count_m,count_f);
}
//按姓名查询并统计多少人符合条件
void query_for_name(struct STUDENT *s,int length)
{
int i,count=0;
char name[10];
printf("请输入要查询的姓名\n");
//gets(name);
scanf("%s",name);
for(i=0;i<length;i++,s++)
{
if(strcmp(name,s->name)==0)
{
printf("%s%2c%5.2f\n",s->name,s->sex,s->total);
count++;
}
}
if(count==0)
printf("没找到符合条件！\n");
else
printf("共找到复合条件的%d个\n",count);
}
void sortBynumber(struct STUDENT *s,int length)
{
int max_id,i,j;
struct STUDENT tmp;//交换的是某个学生的所有信息，所以要定义一个结构体变量
for(i=0;i<length-1;i++)
{
max_id=i;
for(j=i+1;j<length;j++)
{
if(strcmp((s+max_id)->number,(s+j)->number)>0)
max_id=j;
}
tmp=*(s+max_id);*(s+max_id)=*(s+i);*(s+i)=tmp;//*(s+max_id)=stu[max_id]
}
output(s,length);
}
void sortBytotal(struct STUDENT *s,int length)
{
int i,j,max_id;
struct STUDENT temp;
for(i=0;i<length-1;i++)
{
max_id=i;
for(j=i+1;j<length;j++)
{
if((s+max_id)->total<(s+j)->total)
max_id=j;
}
temp=*(s+max_id);*(s+max_id)=*(s+i);*(s+i)=temp;
}
output(s,length);
}
void searchForMaxbytotal(struct STUDENT *s,int length)
{
int max_id=0,i;
for(i=1;i<length;i++)
{
if((s+max_id)->total<(s+i)->total)
max_id=i;
}
printf("总分最高分是%f分，\n该同学的学号为：%s 姓名：%s\n",(s+max_id)->total,(s+max_id)->number,(s+max_id)->name);
}
main()
{
struct STUDENT stu[3];
int choice;
while(1){
display();
printf("请输入你的操作(1-9):\n");
scanf("%d",&choice);
switch(choice)
{
case 1://输入信息
input(stu,3);break;
case 2://输出信息
output(stu,3);break;
case 3://按年龄查询
query_for_age(stu,3);break;
case 4://按性别查询
query_for_sex(stu,3);break;
case 5://按姓名查询
query_for_name(stu,3);break;
case 6://按学号排序
sortBynumber(stu,3);break;
case 7://按总分排序
sortBytotal(stu,3);break;
case 8://查找总分最大
searchForMaxbytotal(stu,3);break;
case 9://退出系统
exit(0);break;
}
getchar();
}
}
