进制转换 | GZTime's Blog

进制转换(最大支持62进制)

很久之前就一直想搞这个东西，一直没有做出来，今天心血来潮写了出来。
因为中间存储数据的是long long所以如果一个进制表达的数字超出范围就无法转换了

Code

#include <bits/stdc++.h>
using namespace std;
class NumConversion
{
  private:
    long long _int_num;
    int _in_sys = 10;
    int _out_sys = 10;
    stack<int> tmp;
    string _in_num;
    string _out_num;
    map<char, int> alpha_num;
    vector<char> num_alpha =
        {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
        'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm',
        'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
        'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M',
        'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z'};

  public:
    NumConversion()
    {
        for (int i = 0; i < 62; i++)
        {
            if (i < 10)
                alpha_num['0' + i] = i;
            else if (i < 36)
                alpha_num['a' + i - 10] = i;
            else
                alpha_num['A' + i - 36] = i;
        }
    }

    long long num_to_dec_int(string num)
    {
        _in_num = num;
        int k = 1;
        long long ans = 0;
        for (int i = _in_num.length() - 1; i >= 0; i--)
        {
            char c = _in_num[i];
            ans += alpha_num[c] * k;
            k *= _in_sys;
        }
        return ans;
    }

    string dec_int_to_num(long long num)
    {
        _out_num.clear();
        while (num)
        {
            tmp.push(num % _out_sys);
            num /= _out_sys;
        }
        while (!tmp.empty())
        {
            _out_num.push_back(num_alpha[tmp.top()]);
            tmp.pop();
        }
        return _out_num;
    }

    void set_num_sys(int in, int out)
    {
        _in_sys = in;
        _out_sys = out;
    }

    string num_converse(string num, int in, int out)
    {
        set_num_sys(in, out);
        _int_num = num_to_dec_int(num);
        return dec_int_to_num(_int_num);
    }
};

int main()
{
    NumConversion *obj = new NumConversion();
    char c;
    while (c != 'n')
    {
        string num;
        int in;
        int out;
        cout << "input number system:\t";
        cin >> in;
        cout << "output number system:\t";
        cin >> out;
        string add = "";
        if (in == 10)
            add = "(dec)";
        else if (in == 8)
            add = "(oct)";
        else if (in == 2)
            add = "(bin)";
        else if (in == 16)
            add = "(hex)";
        cout << "input your number:\t" << add;
        cin >> num;
        if (out == 10)
            add = "(dec)";
        else if (out == 8)
            add = "(oct)";
        else if (out == 2)
            add = "(bin)";
        else if (out == 16)
            add = "(hex)";
        cout << "answer is:\t\t" << add << obj->num_converse(num, in, out) << endl;
        cout << "continue?(y/n):  ";
        cin >> c;
        cout << endl;
    }
    return 0;
}