c语言上机实验报告 (2) 实验六
姓名班级单周上机的那班学号
一
程序源:#include<stdio.h>
#include<stdlib.h>
void main()
{ FILE*fp;
fp=fopen("E:\\yxf01.text","w");
if(fp==NULL)
{
printf("文件打不开");
exit(0);
}
int a,i;
printf("请输入一个尾部为0的整数\n");
scanf("%d",&a);
while(a%10!=0)
{
printf("输入值非法,请从新输入!\n");
scanf("%d",&a);
}
fprintf(fp,"%d=%d+%d+%d+%d+%d+%d+%d+%d+%d+%d\n",a,a/10,a/10,a/10,a/1 0,a/10,a/10,a/
10,a/10,a/10,a/10);
fprintf(fp,"%d=%d+%d+%d+%d+%d+%d+%d+%d+%d\n",a,a/10,a/10,a/10,a/10,a /10,a/10,a/10,a/
10,a-8*(a/10));
fprintf(fp,"%d=%d+%d+%d+%d+%d+%d+%d+%d\n",a,a/10,a/10,a/10,a/10,a/10 ,a/10,a/10,a-7*(a
/10));
fprintf(fp,"%d=%d+%d+%d+%d+%d+%d+%d\n",a,a/10,a/10,a/10,a/10,a/10,a/ 10,a-6*(a/10));
fprintf(fp,"%d=%d+%d+%d+%d+%d+%d\n",a,a/10,a/10,a/10,a/10,a/10,a-
5*(a/10));
fprintf(fp,"%d=%d+%d+%d+%d+%d\n",a,a/10,a/10,a/10,a/10,a-4*(a/10));
fprintf(fp,"%d=%d+%d+%d+%d\n",a,a/10,a/10,a/10,a-3*(a/10));
fprintf(fp,"%d=%d+%d+%d\n",a,a/10,a/10,a-2*(a/10));
fprintf(fp,"%d=%d+%d\n",a,a/10,a-(a/10));
fclose(fp)
}
运行结果:
二
程序源:#include<stdio.h> #include<stdlib.h> #include<math.h> int prime(int x); void main()
{
FILE*fp;
fp=fopen("E:\\yxf02","w");
if(fp==NULL)
{
printf("文件打不开");
exit(0);
}
int n,x,y;
do{
printf("请输入一个大偶数:");scanf("%d",&n);
}while(n<6&&n%2);
x=1;
do
{
x=x+2; y=n-x;
if(prime(x)&&prime(y))
{
printf("%d=%d+%d\n",n,x,y); break;
}
}while(1);
fprintf(fp,"%d=%d+%d",n,x,y); fclose(fp);
}
int prime(int m)
{
int p,flag,k;
k=sqrt(m); flag=1;
for(p=2;p<=k;p++)
if(m%p==0) { flag=0;break;} return flag;
}
运行结果:
三
程序源:#include<stdio.h> void main() {
int m,n=0,d,num;
printf("请输入一个正整数:");
scanf("%d",&m);
while(m!=0)
{ d=m%10;m=m/10;n=n*10+d;}
while(n!=0)
{
d=n%10;n=n/10;printf("%d ",d);
}
}
运行结果:
#include<stdio.h> GCD(int x,int y); void main() {
int x,y,n,i,gcd,lcm,gcd2;
printf("输入两个正整数:\n");
scanf("%d%d",&x,&y);
gcd=GCD(x,y);
lcm=x*y/gcd;
printf("输入整数的个数:\n");
scanf("%d",&n);
i=3;
while(i<=n)
{
printf("输入第i个整数:\n");
scanf("%d",&x);
gcd=GCD(gcd,x);
gcd2=GCD(lcm,x);
lcm=lcm*x/gcd2;
i++;
}
printf("gcd=%d lcm=%d\n",gcd,lcm); }
GCD(int x,int y) {
int r;
r=x%y;
while(r)
{x=y;y=r;r=x%y;}
return y;
}
运行结果:。