任意进制数的加法

实现一个2-35位任意进制的加法。输入有整型表示进制是多少；两个需要相加的字符串。对于不合法的输入输出-1.

比如：

20

jj

10

10j

30

gggt

1

ggh0

程序实现如下：

#include <string>
#include <iostream>

#define MAX_NUM 100000 //最多这么多位字符。发现再多的话程序崩溃
using namespace std;

void reversal(string &s,unsigned long long len)
{
    for (unsigned long long i = 0; i < len / 2; i++)
    {
        char tmp = s[i];
        s[i] = s[len - i - 1];
        s[len - i - 1] = tmp;
    }
}

bool mytoInt(string s, int a[], unsigned long long len,unsigned short N)
{
    for (unsigned long long i = 0; i < len; i++)
    {
        if (s[i] >= '0' && s[i] <= '9')
        {
            a[i] = s[i] - 48;
        }
        else if (s[i] >= 'a' && s[i] <= 'z')
        {
            a[i] = s[i] - 'a' + 10;
        }
        if (a[i] >= N)//判断输入是否合法；比如进制是10，但输入了a这样的字符。
        {
            return true;
        }
    }
    return false;
}
char myInttoChar(int a)
{
    if (a <= 9)
    {
        return a + 48;
    }
    else
    {
        return a + 'a' - 10;
    }
    
}
int main()
{
    unsigned short N;
    string stra, strb;
    
    while (cin >> N )
    {
        int sa[MAX_NUM] = { 0 }, sb[MAX_NUM] = {0};
    
        cin >> stra >> strb;
        if (N < 2 || N > 35)
        {
            cout << -1 << endl;
            break;
        }
        if (stra == "" || strb == "")
        {
            cout << -1 << endl;
            break;
        }
        unsigned long long lena = stra.length();
        unsigned long long lenb = strb.length();
        reversal(stra,lena);
        reversal(strb,lenb);
        bool flag1 = mytoInt(stra, sa,lena,N);
        bool flag2 = mytoInt(strb, sb,lenb,N);
        if (flag1 || flag2)
        {
            cout << -1 << endl;
            break;
        }
        unsigned long long i, j;
        
        if (lena > lenb)//a的长度大于等于b
        {
            i = 0;
            for (i = 0; i < lenb; i++)
            {
                sa[i] = sa[i] + sb[i];
                sa[i + 1] = sa[i + 1] + sa[i] / N;
                sa[i] = sa[i] % N;
            }
            while (sa[i] >= N)//a剩下的位数进行调整；高位
            {
                if (i == lena - 1)
                {
                    int tmp = sa[i] / N;
                    sa[i] = sa[i] % N;
                    cout << myInttoChar(tmp);
                    break;
                }
                sa[i + 1] = sa[i + 1] + sa[i] / N;
                sa[i] = sa[i] % N;
                i++;
            }
            //输出
            unsigned long long max = lena > i ? lena : i;//若最高位有进位则i大
            for (int j = max - 1; j >= 0; j--)
            {
                cout << myInttoChar(sa[j]);
            }
            cout << endl;
        }
        else if (lena < lenb)
        {
            i = 0;
            for (i = 0; i < lena; i++)
            {
                sb[i] = sb[i] + sa[i];
                sb[i + 1] = sb[i + 1] + sb[i] / N;
                sb[i] = sb[i] % N;
            }
            while (sb[i] >= N)
            {
                if (i == lenb - 1)
                {
                    int tmp = sb[i] / N;
                    sb[i] = sb[i] % N;
                    cout << myInttoChar(tmp);
                    break;
                }
                sb[i + 1] = sb[i + 1] + sb[i] / N;
                sb[i] = sb[i] % N;
                i++;
            }
            // 输出
            unsigned long long max = lenb > i ? lenb : i;//若最高位有进位则i大
            for (int j = max - 1; j >= 0; j--)
            {
                cout << myInttoChar(sb[j]);
            }
            cout << endl;
        }
        else if (lena == lenb)
        {
            i = 0;
            for (i = 0; i < lenb - 1; i++)
            {
                sa[i] = sa[i] + sb[i];
                sa[i + 1] = sa[i + 1] + sa[i] / N;
                sa[i] = sa[i] % N;
            }
            sa[i] = sa[i] + sb[i];
            if (sa[i] >= N)
            {
                int tmp = sa[i] / N;
                sa[i] = sa[i] % N;
                cout << myInttoChar(tmp);
            }
            //print
            for (int i = lena - 1; i >= 0; i--)
            {
                cout << myInttoChar(sa[i]);
            }
            cout << endl;
        }
        
    }
    
    return 0;
}