使用函数判断Armstrong 数

include

include

int checkPrimeNumber(int n);
int checkArmstrongNumber(int n);

int main()
{
int n, flag;

printf("输入正整数: ");
scanf("%d", &n);

// 检测素数
flag = checkPrimeNumber(n);
if (flag == 1)
    printf("%d 是素数。\n", n);
else
    printf("%d 不是素数\n", n);

// 检测 Armstrong 数
flag = checkArmstrongNumber(n);
if (flag == 1)
    printf("%d 是 Armstrong 数。", n);
else
    printf("%d 不是 Armstrong 数。",n);
return 0;

}

int checkPrimeNumber(int n)
{
int i, flag = 1;

for(i=2; i<=n/2; ++i)
{

// 非素数条件
    if(n%i == 0)
    {
        flag = 0;
        break;
    }
}
return flag;

}

int checkArmstrongNumber(int number)
{
int originalNumber, remainder, result = 0, n = 0, flag;

originalNumber = number;

while (originalNumber != 0)
{
    originalNumber /= 10;
    ++n;
}

originalNumber = number;

while (originalNumber != 0)
{
    remainder = originalNumber%10;
    result += pow(remainder, n);
    originalNumber /= 10;
}

// 判断条件
if(result == number)
    flag = 1;
else
    flag = 0;

return flag;

}

输出结果为：

输入正整数: 371
371 不是素数
371 是 Armstrong 数。