C语言程序设计教程（第三版）课后习题5.7 （C语言代码）

解题思路:
先分出位数，进行分类讨论



注意事项:





参考代码:

/*拆分数字*/

#include<stdio.h>

int main()

{

int x;

scanf("%d",&x);

if(x>=0&&x<=9)

{

printf("1\n");

printf("x\n");

printf("x\n");

}

else if(x>=10&&x<=99)

{

int a,b;

a = x%10;

b = x/10;

printf("2\n");

printf("%d %d\n",b,a);

printf("%d%d\n",a,b);

}

else if(x>=100&&x<=999)

{

int a1,b1,c1;

a1 = x/100;

b1 = (x%100)/10;

c1 = (x%100)%10;

printf("3\n");

printf("%d %d %d\n",a1,b1,c1);

printf("%d%d%d\n",c1,b1,a1);

}

else if(x>=1000&&x<=9999)

{

int a2,b2,c2,d2;

a2 = x/1000;

b2 = (x%1000)/100;

c2 = ((x%1000)%100)/10;

d2 = ((x%1000)%100)%10;

printf("4\n");

printf("%d %d %d %d\n",a2,b2,c2,d2);

printf("%d%d%d%d\n",d2,c2,b2,a2);

}

else

{

int a3,b3,c3,d3,e3;

a3 = x/10000;

b3 = (x%10000)/1000;

c3 = ((x%10000)%1000)/100;

d3 = (((x%1000)%100)%100)/10;

e3 = (((x%1000)%100)%100)%10;

printf("5\n");

printf("%d %d %d %d %d\n",a3,b3,c3,d3,e3);

printf("%d%d%d%d%d\n",e3,d3,c3,b3,a3);

}

return 0;

}