题解 | #坐标移动#不使用库函数，自己实现各个功能

#include <iostream>
#include <string>
#include <vector>
using namespace std;

string legal = "ADWS";  // 方向指令的合法字符
bool find_legal(char a) {
    for (int i = 0; i < 4; i++) {
        if (a == legal[i])
            return true;
    }
    return false;
}

vector<string> first(string input) {//对输入的字符串进行切割
    int input_size = input.size();
    vector<string> result;
    int left = 0;
    for (int right = 0; right < input_size; right++) {
        if (input[right] == ';') {
            
            string now = input.substr(left, right - left);
            if (!now.empty()) {  
                result.push_back(now);
            }
            left = right + 1; 
        }
    }
    return result;
}

vector<string> is_legal(const vector<string>& first) {//判断字符串是否合法，传入first函数处理得到的字符串
    vector<string> result;
    for (const string& command : first) {
        int nums_size = command.size();
        if (nums_size >= 2 && nums_size <= 3) {
            if (find_legal(command[0])) { 
                bool valid = true;
                for (int k = 1; k < nums_size; k++) {
                    if (!(command[k] >= '0' && command[k] <= '9')) {
                        valid = false;
                        break;
                    }
                }
                if (valid) {
                    result.push_back(command); 
                }
            }
        }
    }
    return result;
}

int main() {
    int x = 0, y = 0;
    string input;
    cin >> input;
    vector<string> legal_input = is_legal(first(input));
    for (const string& command : legal_input) {
        int move_cost = command.substr(1).empty() ? 0 : stoi(command.substr(1)); 
        
        if (command[0] == 'A') {
            x -= move_cost; 
        } else if (command[0] == 'D') {
            x += move_cost; 
        } else if (command[0] == 'W') {
            y += move_cost; 
        } else if (command[0] == 'S') {
            y -= move_cost; 
        }
    }
    
    cout << x << ',' << y << endl; 
}