Question

给定一个不多于5位的正整数，要求：① 求它是几位数；② 分别打印出每一位数字；③ 按逆序打印出各位数

#include <stdio.h>
main()
{ long int num;
int indiv,ten,hundred,thousand,ten_thousand,place;
printf("请输入一个整数（0~99999）：");
scanf("%ld",&num);
if (num>9999) place=5;
else if(num>999) place=4;
else if(num>99) place=3;
else if(num>9) place=2;
else place=1;
printf("place =%d\n", place);
ten_thousand=num/10000;
thousand=num/1000%10;
hundred=num/100%10; /*求高手具体解析下这个位置,要是num=89830是怎样的解析思路*/
ten=num%100/10;
indiv=num%10;
switch(place)
{ case 5: printf("%d,%d,%d,%d,%d",ten_thousand,thousand,hundred,ten,indiv);
printf("\n反序数字为；");
printf("%d%d%d%d%d\n",indiv,ten,hundred,thousand,ten_thousand);
break;
case 4: printf("%d,%d,%d,%d",thousand,hundred,ten,indiv);
printf("\n反序数字为：");
printf("%d%d%d%d\n",indiv,ten,hundred,thousand);
break;
case 3: printf("%d,%d,%d",hundred,ten,indiv);
printf("\n反序数字为：");
printf("%d%d%d\n",indiv,ten,hundred);
break;
case 2: printf("%d,%d",ten,indiv);
printf("\n反序数字为：");
printf("%d%d\n",indiv,ten);
break;
case 1: printf("%d",indiv);
printf("\n反序数字为：");
printf("%d\n",indiv);
break;
}
}

Answer 1

#include <stdio.h>
main()
{
long m,a,b,c,d,e;
printf("请输入一个整数:(0~99999):\n");
scanf("%ld",&m);
e=m%10;
d=m/10%10;
c=m/100%10;
b=m/1000%10;
a=m/10000%10;
if(m>=10000&&m<=99999)
{
printf("你输入的是5位数.\n");
printf("%ld %ld %ld %ld %ld.\n",a,b,c,d,e);
printf("逆序输出:%ld.\n",e*10000+d*1000+c*100+b*10+a);
}
else if(m>=1000)
{
printf("你输入的是4位数.\n");
printf("%ld %ld %ld %ld.\n",b,c,d,e);
printf("逆序输出:%ld.\n",e*1000+d*100+c*10+b);
}
else if(m>=100)
{
printf("你输入的是3位数.\n");
printf("%ld %ld %ld.\n",c,d,e);
printf("逆序输出:%ld.\n",e*100+d*10+c);
}
else if(m>=10)
{
printf("你输入的是2位数.\n");
printf("%ld %ld.\n",d,e);
printf("逆序输出:%ld.\n",e*10+d);
}
else if(m>=0)
{
printf("你输入的是1位数.\n");
printf("%ld\n",e);
printf("逆序输出:%ld.\n",e);
}
getch();
}

Answer 2

#include <stdio.h>
main()
{
long m,a,b,c,d,e;
printf("请输入一个整数:(0~99999):\n");
scanf("%ld",&m);
e=m%10;
d=m/10%10;
c=m/100%10;
b=m/1000%10;
a=m/10000%10;
if(m>=10000&&m<=99999)
{
printf("你输入的是5位数.\n");
printf("%ld %ld %ld %ld %ld.\n",a,b,c,d,e);
printf("逆序输出:%ld.\n",e*10000+d*1000+c*100+b*10+a);
}
else if(m>=1000)
{
printf("你输入的是4位数.\n");
printf("%ld %ld %ld %ld.\n",b,c,d,e);
printf("逆序输出:%ld.\n",e*1000+d*100+c*10+b);
}
else if(m>=100)
{
printf("你输入的是3位数.\n");
printf("%ld %ld %ld.\n",c,d,e);
printf("逆序输出:%ld.\n",e*100+d*10+c);
}
else if(m>=10)
{
printf("你输入的是2位数.\n");
printf("%ld %ld.\n",d,e);
printf("逆序输出:%ld.\n",e*10+d);
}
else if(m>=0)
{
printf("你输入的是1位数.\n");
printf("%ld\n",e);
printf("逆序输出:%ld.\n",e);
}
getch();
}

Answer 3

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main()
{
    char a[99];
    gets(a);
    int i=strlen(a);
    char *p=a;
    printf("%d位数\n",i);
    while(*p)
    {
        printf("%c",*p);
        *p++;
    }
    return 0;
}