题解 | #坐标移动#

#include <iostream>
#include <string>

using namespace std;

class Solution
{
  public:
    void Cal_Pos(const string& pos_str)
    {
        int n = pos_str.size()-1;
        if(n <= 1)
            return;
        int dir_p,p1,p2;
        p1 = 1;p2 = 0;
        dir_p = p2;
        bool nn_flag = 0;
        
        while(p1 <= n)
        {
             //方向符号位置为分号，往后移动一位
            while(pos_str[dir_p] == ';' )
            {
                ++p1;
                ++p2;
                ++dir_p;
            }
            //第一个不是方向字符
            if( !IsDirect_Char(pos_str[dir_p]) )
            {
                while(pos_str[p1] != ';')
                    p1++;
                //开始下一个判断
                p2 = p1 + 1;
                p1 = p2 + 1;
                dir_p = p2;
            
            }
            else//第一个是方向字符
            {
                while(pos_str[p1] != ';')
                {
                     if( !IsNum_char(pos_str[p1]) )//发现不是数字，则设置标志
                         nn_flag = 1;
                     p1++;
                }
                //当前p1所指向为分号位置
                if(!nn_flag)//全为数字
                {
                    //提取方向字符与有效数字
                     char tmp_dir = pos_str[dir_p];
                    int Len = p1 - p2 - 1;
                    string tmp_str = pos_str.substr(p2+1,Len);
                    int tmp_data = stoi(tmp_str);
                    //计算对应坐标
                    Cal_Distance(tmp_dir,tmp_data); 
                }
                //更新下一次
                p2 = p1 + 1;
                p1 = p2 + 1;
                dir_p = p2;
                nn_flag = 0;//清除本次的标志
            }
            
        }
           
    }
    void Cal_Distance(char c,int data)
    {
        switch (c)
        {
            case 'A':
                x_sum -= data;
                break;
            case 'D':
                x_sum += data;
                break;
            case 'W':
                y_sum += data;
                break;
            case 'S':
                y_sum -= data;
                break;
        }
    }
    bool IsNum_char(char c)const
    {
        if( ((c-'0') >= 0) && ((c-'0') <= 9) )
            return true;
        return false;
    }
    
    bool IsDirect_Char(char c)const
    {
        if(c == 'A' || c == 'D' || c == 'W' || c == 'S')
            return true;
        return false;
    }
    int GetX_sum()const
    {
        return x_sum;
    }
    
    int GetY_sum()const
    {
        return y_sum;
    }
    
    Solution(int x,int y)
        :x_sum(0),y_sum(0)
        {
            
        }
  private:
    int x_sum;
    int y_sum;
};

int main()
{
    string pos_str;
    getline(cin, pos_str);
    Solution s(0,0);
   // cout << s.IsNum_char('2') << endl;
    s.Cal_Pos(pos_str);
    cout << s.GetX_sum() << "," << s.GetY_sum() << endl;
    return 0;
}