打印从1到最大的n位数

题目：输入数字n,顺序打印从1到最大n位的十进制数，例如输入3，打印1到999

#include<iostream>

bool Increment(char* number);
void PrintNumber(char* number);
void PrintToMaxOfNDigitsRecursively(char*number, int length, int index);

//方法一：字符数组上
void PrintToMaxOfNDigits(int n)
{
//判断边界
	if (n <= 0)
		return;
//创建一个字符数组，长度位n+1(包含结尾 ‘、0’）
	char* number = new char[n + 1];
//初始化数组
	memset(number, '0', n);
//以'\0'结尾
	number[n] = '\0';
	while (!Increment(number))
		PrintNumber(number);
	delete[] number;
}

bool Increment(char* number)
{
//溢出位
	bool isOverflow = false;
//进位
	int nTakerOver = 0;
	int nLength = strlen(number);
//number[nLength-1]为倒数第一位（除'\0')
	for (int i = nLength - 1;i >= 0;--i)
	{
		int nSum = number[i] - '0' + nTakerOver;
//如果是个位，则加一
		if (i == nLength - 1)
			++nSum;
		if (nSum >= 10)
		{
//如果nSum>=10且i为个位时，表示溢出
			if (i == 0)
				isOverflow = true;
//否则减十，进位加一
			else
			{
				nSum -= 10;
				nTakerOver = 1;
				number[i] = '0' + nSum;
			}
		}
//当nSum小于10时，结束循环
		else
		{
			number[i] = '0' + nSum;
			break;
		}
	}
	return isOverflow;
}
//方法二：用数组递归
void PrintToMaxOfNDigits2(int n)
{
//判断边界
	if (n <= 0)
		return;
//创建字符数组
	char* number = new char[n + 1];
//数组以'\0'结尾
	number[n] = '\0';
//打印
	for (int i = 0;i < 10;++i)
	{
		number[0] = '0' + i;
		PrintToMaxOfNDigitsRecursively(number, n, 0);
	}
//最后还要释放数组内存
	delete[] number;
}

void PrintToMaxOfNDigitsRecursively(char*number, int length, int index)
{
//当最高位是个位时直接打印
	if (index == length - 1)
	{
		PrintNumber(number);
		return;
	}
//否则index+1,打印下一位，递归调用函数
	for (int i = 0;i < 10;++i)
	{
		number[index + 1] = '0' + 1;
		PrintToMaxOfNDigitsRecursively(number, length, index + 1);
	}
}

void PrintNumber(char* number)
{
	bool isBeginning0 = true;
	int nLength = strlen(number);
	for (int i = 0;i < nLength;++i)
	{
//当当前数位不为0时打印 
		if (isBeginning0&&number[i] != '\0')
			isBeginning0 = false;
		if (!isBeginning0)
			printf("%c", number[i]);
	}
	printf("\t");
}

int main()
{
	PrintToMaxOfNDigits(0);
	printf("\n\n");
	PrintToMaxOfNDigits2(0);
	printf("\n\n");

	PrintToMaxOfNDigits(1);
	printf("\n\n");
	PrintToMaxOfNDigits2(1);
	printf("\n\n");

	PrintToMaxOfNDigits(2);
	printf("\n\n");
	PrintToMaxOfNDigits2(2);
	printf("\n\n");

	PrintToMaxOfNDigits(3);
	printf("\n\n");
	PrintToMaxOfNDigits2(3);
	printf("\n\n");

	return 0;
}