（Problem 34）Digit factorials

145 is a curious number, as 1! + 4! + 5! = 1 + 24 + 120 = 145.

Find the sum of all numbers which are equal to the sum of the factorial of their digits.

Note: as 1! = 1 and 2! = 2 are not sums they are not included.

题目大意：

145 是一个奇怪的数字, 因为 1! + 4! + 5! = 1 + 24 + 120 = 145.

找出所有等于各位数字阶乘之和的数字之和。

注意: 因为 1! = 1 和 2! = 2 不是和的形式，所以它们不算在内。

//（Problem 34）Digit factorials
// Completed on Thu, 25 Jul 2013, 16:11
// Language: C
//
// 版权所有（C）acutus   (mail: [e-mail])
// 博客地址：http://www.cnblogs.com/acutus/#include<stdio.h>
#include<math.h>
#include<stdbool.h>

int factorial(int n)   //阶乘函数
{
    if(n== || n==) return ;
    else return n*factorial(n-);
}

bool judge(int n)   //判断一个整数是否符合题意的函数
{
    char s[];
    sprintf(s,"%d",n);
    int len=strlen(s);
    int sum=;
    for(int i=; i<len; i++)
    {
        sum+=factorial(s[i]-'');
    }
    if(n==sum) return true;
    else return false;
}

int main()
{
    int sum=;
    for(int i=; i<; i++)
    {
        if(judge(i))
            sum+=i;
    }
    printf("%d\n",sum);
    return ;
}

Answer:

40730