算法15---数论3---水仙花数

算法15---数论3---水仙花数

简单地说。三维正整数在树枝上等于其各位数字的立方之和，称为水仙花数；

同样我们也可以定义一些更高等级的水仙花数，比如4位的，例如1634，1634位1,6,3,4的四次方和。

 

//
/*
    题目：水仙花数
    author taoliu——alex  2016.10

    主要实现：
    1 找出给定位数内的水仙花数；
    2 判断一个数是不是水仙花数；

*/



#include <stdio.h>
#include <math.h>


//输出n为的水仙花数

void shuixianhua(int n)
{
    long start,end;
    long sum;

    start=(long)pow(10,n-1);
    end=(long)pow(10,n)-1;
    for (long i = start; i <=end; i++)
    {
        long num=i;
        sum=0;
        for (int j = 0; j < n; j++)
        {
            long temp=num%10;
            sum=sum+(long)pow(temp,n);
            num=(num-temp)/10;
        }
        if (sum==i)
        {
            printf("%ld
",i);
        }

    }
}


void  shuixianhua_judge(long n)
{
    int digit=1;
    long sum=0;
    long temp ;
    long num=n;
    long num2=n;
    while (num/10!=0)
    {
        digit=digit+1;
        num=num/10;
    }
    printf("the digit is %d
", digit);


    for (int i = 0; i < digit; i++)
    {
        temp=num2%10;
        //printf("%ld
",temp);
        sum=sum+(long)pow(temp,digit);
        printf("%ld
",sum );
        num2=(num2-temp)/10;
    }
    //printf("%ld
",sum);
    if (sum==n)
    {
        printf("%ld is shuixianhua number
",n);
    }
    else
        printf("%ld is NOT shuixianhua number
",n);

}


int main()
{
     long num;
     printf("please input the number you want to judge!
");
     scanf("%ld",&num);
     shuixianhua_judge(num);


     int n;
     printf("give the digit you want to find!
");
     scanf("%d",&n);
     shuixianhua(n);

     return 0;
}