基于c++的完全数之TDD版本

#include <iostream>#include <cassert>#include <cmath>using namespace std;//完全数，真因子之和等于该数//1.需要判断一个数是否为因子//2.需要获得所有真因子之和//3.需要判断是否是完全数bool is_factor(int factor, int num){    return num % factor == 0;}static int add_factor(int factor, int num){    return factor + num / factor;}static int cal_aliquot_sum(int num){    int sum = 1;    for (int i = 2; i <= (int)sqrt((double)num); i++)    {        if (is_factor(i, num))        {            sum += add_factor(i, num);        }    }    return sum;}int aliquot_sum(int num){    int sum = 0;    if (num > 0)    {        sum = cal_aliquot_sum(num);    }    return sum;}bool is_perfect(int num){    return aliquot_sum(num) == num;}bool is_abundant(int num){    return aliquot_sum(num) > num;}bool is_deficient(int num){    return aliquot_sum(num) < num;}/* ------------------------------- */void test_1_is_factor_of_10(){    assert(is_factor(1, 10));}void test_10_is_factor_of_10(){    assert(is_factor(10, 10));}void test_3_is_not_factor_of_10(){    assert(!is_factor(3, 10));}void test_aliquot_sum_of_6(){    assert(6 == aliquot_sum(6));}void test_aliquot_sum_of_28(){    int sum = 1 + 28 + 2 + 14 + 4 + 7 - 28;    assert(sum == aliquot_sum(28));}void test_aliquot_sum_of_negative(){    assert(0 == aliquot_sum(-20));}void test_aliquot_sum_of_max_int(){    assert(1 == aliquot_sum(2147483647));}void test_the_first_five_perfect(){    assert(is_perfect(6));    assert(is_perfect(28));    assert(is_perfect(496));    assert(is_perfect(8128));    assert(is_perfect(33550336));}static const int PERFECT_NUMS[] = {6, 28, 496, 8128, 33550336};bool find_num_in(int num, const int *perfects, int size){    bool found = false;    int i = 0;    while (!found && i < size)    {        if (perfects[i++] == num)        {            found = true;        }    }    return found;}void test_non_perfect(){    int size = sizeof(PERFECT_NUMS) / sizeof(int);    for (int i = 2; i < 10000; i++)    {        if (find_num_in(i, PERFECT_NUMS, size))        {            assert(is_perfect(i));        }        else        {            assert(!is_perfect(i));        }    }}int main(){    test_1_is_factor_of_10();    test_10_is_factor_of_10();    test_3_is_not_factor_of_10();        test_aliquot_sum_of_6();    test_aliquot_sum_of_28();    test_aliquot_sum_of_negative();    test_aliquot_sum_of_max_int();        test_the_first_five_perfect();    test_non_perfect();        return 0;}