剑指offer第3章学习：高质量的代码

1.一个很重要的问题，你写代码的时候，变量名称一定要有章法，不能随便起。

2.代码书写尽可能的清晰。

//test 11
double Power_Recursively(double base, unsigned int exponent)
{
    if (exponent == 0)
        return 1;
    
    if (exponent == 1)
        return base;
    
    double result = Power_Recursively(base, exponent >>1);
    
    if (exponent & 0x01 == 1)
        result *= base;
    
    return result;
}
bool equal(double num1, double num2)
{
    if (num1 - num2 <= 0.0000001&&num1 - num2 >= -0.0000001)
        return true;
    else
        return false;
}
bool g_InValidInput = false;
double Power(double base, int exponent)
{
    
    g_InValidInput = false;
    if (equal(base, 0.0) && exponent == 0)
    {
        g_InValidInput = true;
        return 0.0;
    }

    unsigned int AbsExponent = (unsigned int)exponent;
    if (exponent < 0)
        unsigned int AbsExponent = (unsigned int)(-1 * exponent);

    double result = Power_Recursively(base, AbsExponent);

    return result;
}

//test 12 打印1到最大的n位数
bool Increment(char* number)
{
    bool IsOverflow = false;
    int nTakeOver = 0;
    int nLength = strlen(number);//得到字符串的长度

    for (int i = nLength - 1; i >= 0; --i)//从字符串的最后一位向前判断
    {
        int nSum = number[i] - '0' + nTakeOver;
        if (i == nLength - 1)
            nSum++;
        if (nSum >= 10)
        {
            if (i == 0)
                IsOverflow = true;
            else
            {
                nSum -= 10;
                nTakeOver = 1;
                number[i] = '0' + nSum;
            }
        }
        else
        {
            number[i] = '0' + nSum;
            break;
        }
    }
    return IsOverflow;
}

void PrintNumber(char* number)
{
    bool IsBeginning0 = true;
    int nLength = strlen(number);
    for (int i = 0; i < nLength; ++i)
    {
        if (IsBeginning0&&number[i] != '0')
            IsBeginning0 = false;
        if (!IsBeginning0)
            cout << number[i];
    }
}
void Print1toMaxOfDigits(int n)
{
    if (n <= 0)
        return;
    char *number = new char[n + 1];
    memset(number, '0', n);
    number[n] = '';

    while (!Increment(number))
        PrintNumber(number);

    delete[]number;
}