剑指Offer10 打印1到最大n位数

/*************************************************************************
    > File Name: 10_PrintToMaxNum.c
    > Author: Juntaran
    > Mail: JuntaranMail@gmail.com
    > Created Time: 2016年08月30日 星期二 00时47分36秒
 ************************************************************************/

#include <stdio.h>
#include <malloc.h>
#include <string.h>


void PrintNumber(char* number)
{
    bool isBeginning0 = true;
    int length = strlen(number);
    
    for (int i = 0; i < length; ++i)
    {
        if (isBeginning0 && number[i]!='0')
            isBeginning0 = false;
        
        if (!isBeginning0)
            printf("%c", number[i]);
    }
    printf("	");
}


bool Increment(char* number)
{
    bool isOverflow = false;
    int length = strlen(number);
    int TakeOver = 0;
    
    for (int i = length-1; i >= 0; i--)
    {
        int sum = number[i] - '0' + TakeOver;    // 进位
        if (i == length - 1)
            sum ++;
        
        if (sum >= 10)
        {
            if (i == 0)
                isOverflow = true;
            else
            {
                sum -= 10;
                TakeOver = 1;
                number[i] = sum + '0';
            }
        }
        else
        {
            number[i] = sum + '0';
            break;
        }
    }
    return isOverflow;
}

// 从1打印到最大的n位数
void PrintToMaxNum1(int n)
{
    if (n <= 0)
        return;
    
    char* number = (char*)malloc(sizeof(char)*(n+1));
    memset(number, '0', n);
    number[n] = '';
    
    while (!Increment(number))
    {
        PrintNumber(number);
    }
    free(number);
}


/************************************************************************/
// 递归写法
void PrintToMaxNumRecursively(char* number, int length, int index)
{
    if (index == length-1)
    {
        PrintNumber(number);
        return;
    }
    for (int i = 0; i < 10; ++i)
    {
        number[index+1] = i + '0';
        PrintToMaxNumRecursively(number, length, index+1);
    }
}

void PrintToMaxNum2(int n)
{
    if (n <= 0)
        return;
    
    char* number = (char*)malloc(sizeof(char)*(n+1));
    number[n] = '';
    
    for (int i = 0; i < 10; ++i)
    {
        number[0] = i + '0';
        PrintToMaxNumRecursively(number, n, 0);
    }
    free(number);
}


int main()
{
    int n = 5;
    PrintToMaxNum1(n);
    PrintToMaxNum2(n);
}