#include<stdio.h>
int main(void)
{
struct student
{int num;
char name[30];
double score;
}stu;
int n,i;
double sum=0.0;
while(printf("输入n:"),scanf("%d",&n),n>=10||n<+0);
for(i=0;i<n;i++)
{
printf("输入第%d个学生的学号、姓名和成绩:",i+1);
scanf("%d%s%lf",&stu.num,&stu.name,&stu.score);
sum+=stu.score;
}
printf("平均成绩：%.2f\n",sum/n);
return 0;
}

#include<stdio.h>
int main(void)
{
struct complex
{
int a,b;
}x,y,z;
printf("输入a1,a2,b1,b2:");
scanf("%d%d%d%d",&x.a,&x.b,&y.a,&y.b);
z.a=x.a*y.a-x.b*y.b;
z.b=x.a*y.b+x.b*y.a;
printf("(%d+%di)x(%d+%di=%d+%di)\n",x.a,x.b,y.a,y.b,z.a,z.b);
return 0;
}

#include<stdio.h>
int main(void)
{
struct book
{
char name[80];
double price;
}book,min,max;
int n,i;
do
{ printf("输入n:");
scanf("%d",&n);
}while(n>=10||n<=0);
printf("输入第1本书的名称和定价:");
scanf("%s%lf",book.name,&book.price);
max=min=book;
for(i=1;i<n;i++)
{
printf("输入第%d本书的名称和定价:",i+1);
scanf("%s%lf",book.name,&book.price);
if(min.price>book.price)min=book;
if(max.price<book.price)max=book;
}
printf("价格最高的书:%s,价格:%.1f\n",max.name,max.price);
printf("价格最低的书:%s,价格:%.1f\n",min.name,min.price);
return 0;
}

#include<stdio.h>
struct addres
{char name[20];
int birthday;
char phon[80];
};
int main(void)
{
void bubble(struct addres *, int n);
struct addres person[0];
int n,i;
while(printf("输入n:"),scanf("%d",&n),n>=10||n<=0);
for(i=0;i<n;i++)
{
printf("输入第%d个人的姓名、生日、电话号码:",i+1);
scanf("%s &d %s\n",person[i].name,person[i].birthday,person[i].phon);
}
bubble(person,n);
for(i=0;i<n;i++);
printf("%s %d %s\n",person[i].name,person[i].birthday,person[i].phon);
return 0;
}
void bubble(struct addrres *p,int n)
{
int i,j;
struct addres temp;
for(i=1;i<n-1;i++)
{
for(j=0;j<n-1;j++)
if(p[j].birthday>p[j+1].birthday)
{temp=p[j];
p[j]=p[j+1];
p[j+1]=temp;
}
}
}

尼玛就算我不玩DNF了也要还钱！

#include<stdio.h>
#include<math.h>
int main(void)
{
FILE *p;
int x,y,x1,y1;float z, z1;
x1=y1=0;
z1=10*cos(x1-4)+5*sin(y1-2);
for(x=0;x<=10;x++)
for(y=0;y<=10;y++)
{
z=10*cos(x-4)+5*sin(y-2);
if(z1>z)
{
x1=x;
y1=y;
z1=z;
}
}
p=fopen("e:\\Paper \\design.dat","w" );
fprintf(p,"%d,%d",x1,y1);
fclose(p);
return 0;
}

#include <stdio.h>
#include <stdlib.h>
int main(void)
{
char ch;
int a=0,b=0,c=0;
FILE *fp;
if((fp=fopen("b.txt","w")) == NULL)
{
printf("Can't Open File!");
exit(0);
}
printf("输入文本：");
while((ch=getchar())!='\n')
fputc(ch,fp);
if(fclose(fp))
{
printf("Cant't close the file!");
exit(0);
}
if((fp=fopen("b.txt","r"))==NULL)
{
printf("Cant't close the file!3");
exit(0);
}
for(ch=fgetc(fp);ch!=EOF;ch=fgetc(fp))
{
if(ch>='a'&&ch<='z'||ch>='A'&&ch<='Z') a++;
else if(ch>='0'&&ch<='9') b++;
else c++;
}
if(fclose(fp))
{
printf("Cant't close the file!4");
exit(0);
}
printf("字母:%d,数字:%d,其他字符:%d\n",a,b,c);
return 0;
}

#include<stdio.h>
int main()
{
FILE *p;int n,i,s;
p=fopen("E:\\Paper\\design.dat","w");
for(n=6;n<=10000;n++)
{
s=1;
for(i=2;i<=n/2;i++)
if(n%i==0)s+=i;
if(s==n) fprintf(p,"%6d",n);
}
fclose(p);
return 0;
}