打印1到最大的N位数

9

分析：

这是一个大数问题，利用字符串模拟运算。

#include<cstdio>
#include<cstring>
#include<cstdlib>

bool Increment(char* number)
{
    bool isOverflow = false;
    int nTakeOver = 0;
    int nLength = strlen(number);
    for(int i = nLength - 1; i >= 0; i--)
    {
        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)
        {
            printf("%c",number[i]);
        }
    }
    printf("\n");
}

void Print1ToMaxOfNDigits(int n)
{
    if(n <= 0)
        return;
    char *number = new char[n+1];
    memset(number,'0',n);
    number[n] = '\0';
    while(!Increment(number))
    {
        PrintNumber(number);
    }
    delete []number;
}

int main()
{
    int n;
    while(scanf("%d",&n) != EOF)
    {
        Print1ToMaxOfNDigits(n);
    }
    return 0;
}

#include<cstdio>
#include<cstring>
#include<cstdlib>

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)
        {
            printf("%c",number[i]);
        }
    }
    printf("\n");
}

void Print1ToMaxOfNDigitsRecursively(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';
        Print1ToMaxOfNDigitsRecursively(number,length,index+1);
    }
}

void Print1ToMaxOfNDigits(int n)
{
    if(n <= 0)
    {
        return;
    }
    char* number = new char[n+1];
    number[n] = '\0';
    for(int i = 0; i < 10; i++)
    {
        number[0] = i+'0';
        Print1ToMaxOfNDigitsRecursively(number,n,0);
    }
    delete[] number;
}



int main()
{
    int n;
    while(scanf("%d",&n) != EOF)
    {
        Print1ToMaxOfNDigits(n);
    }
    return 0;
}

打印1到最大的N位数

原文：http://blog.csdn.net/biluyang/article/details/44063553