[PAT-A] 1082 Read Number in Chinese

Java

import java.io.*;
import java.util.*;

public class Main {
    static String[] num1 = {
            "ling", "yi", "er", "san", "si",
            "wu", "liu", "qi", "ba", "jiu",
    };
    static String[] num2 = {"", "Shi", "Bai", "Qian"};
    static String[] num3 = {"", "Wan", "Yi"};

    static boolean checkLing(String s) {
        return s.endsWith("ling ");
    }

    static String convert(int n) {
        List<Integer> nums = new ArrayList<>();
        while (n > 0) {
            nums.add(n % 10);
            n /= 10;
        }

        StringBuilder res = new StringBuilder();
        for (int i = nums.size() - 1; i >= 0; --i) {
            int t = nums.get(i);
            if (t != 0) res.append(num1[t]).append(" ");
            else if (!checkLing(res.toString())) res.append("ling ");
            if (t != 0 && i > 0) res.append(num2[i]).append(" ");
        }

        while (checkLing(res.toString())) res = new StringBuilder(res.substring(0, res.length() - 5));
        return res.toString();
    }

    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        int n = Integer.parseInt(br.readLine());

        if (n == 0) {
            System.out.println("ling");
        } else {
            if (n < 0) {
                System.out.print("Fu ");
                n = -n;
            }

            List<Integer> nums = new ArrayList<>();
            while (n > 0) {
                nums.add(n % 10000);
                n /= 10000;
            }

            StringBuilder res = new StringBuilder();
            for (int i = nums.size() - 1; i >= 0; --i) {
                int t = nums.get(i);
                if (res.length() > 0 && t < 1000 &&
                        !(res.length() >= 5 && res.substring(res.length() - 5).equals("ling ")))
                    res.append("ling ");
                if (t != 0) res.append(convert(t));
                if (t != 0 && i > 0) res.append(num3[i]).append(" ");
            }

            while (checkLing(res.toString())) res = new StringBuilder(res.substring(0, res.length() - 5));
            if (res.length() > 0) res.setLength(res.length() - 1);
            System.out.println(res);
        }

        br.close();
    }
}

C++

#include <iostream>
#include <cstring>
#include <algorithm>
#include <vector>

using namespace std;

string num1[10] = {
        "ling", "yi", "er", "san", "si",
        "wu", "liu", "qi", "ba", "jiu",
};
string num2[4] = {"", "Shi", "Bai", "Qian"};
string num3[3] = {"", "Wan", "Yi"};

bool check_ling(string s) {
    return s.size() >= 5 && s.substr(s.size() - 5) == "ling ";
}

string convert(int n) {
    vector<int> nums;
    while (n) {
        nums.push_back(n % 10);
        n /= 10;
    }

    string res;
    for (int i = nums.size() - 1; i >= 0; --i) {
        int t = nums[i];
        if (t != 0) res += num1[t] + " ";
        else if (!check_ling(res)) res += "ling ";
        if (t != 0 && i) res += num2[i] + " ";
    }

    while (check_ling(res)) res = res.substr(0, res.size() - 5);
    return res;
}

int main() {
    int n;
    cin >> n;
    if (n == 0) cout << "ling";
    else {
        if (n < 0) {
            cout << "Fu ";
            n = -n;
        }

        vector<int> nums;
        while (n) {
            nums.push_back(n % 10000);
            n /= 10000;
        }

        string res;
        for (int i = nums.size() - 1; i >= 0; --i) {
            int t = nums[i];
            if (res.size() && t < 1000 &&
                !(res.size() >= 5 && res.substr(res.size() - 5) == "ling "))
                res += "ling ";
            if (t != 0) res += convert(t);
            if (t != 0 && i) res += num3[i] + " ";
        }

        while (check_ling(res)) res = res.substr(0, res.size() - 5);
        res.pop_back();
        cout << res;
    }
    return 0;
}