String-mainipulation10

发表于 分类于 ，

题目描述[原题链接][https://leetcode-cn.com/problems/integer-to-english-words/]

将非负整数转换为其对应的英文表示。可以保证给定输入小于 2的31次方 - 1 。

示例 1:

输入: 123
输出: “One Hundred Twenty Three”

示例 2:

输入: 12345
输出: “Twelve Thousand Three Hundred Forty Five”

示例 3:

输入: 1234567
输出: “One Million Two Hundred Thirty Four Thousand Five Hundred Sixty Seven”

示例 4:

输入: 1234567891
输出: “One Billion Two Hundred Thirty Four Million Five Hundred Sixty Seven Thousand Eight Hundred Ninety One”

算法描述

​ 考察英文水平><___

C++代码

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
class Solution {
public:
    int hundred = 100, thousand = 1000, million = 1000000, billion = 1000000000;
    unordered_map<int, string> numbers;

    string numberToWords(int num) {
        char number20[][30] = {"Zero", "One", "Two", "Three", "Four", "Five", 
                               "Six", "Seven", "Eight", "Nine", "Ten", "Eleven", 
                               "Twelve", "Thirteen", "Fourteen", "Fifteen", 
                               "Sixteen", "Seventeen", "Eighteen", "Nineteen"};
        char number2[][30] = {"Twenty", "Thirty", "Forty", "Fifty", "Sixty", 
                              "Seventy", "Eighty", "Ninety"};
        for (int i = 0; i < 20; i ++ ) numbers[i] = number20[i];
        for (int i = 20, j = 0; i < 100; i += 10, j ++ ) numbers[i] = number2[j];
        numbers[hundred] = "Hundred", numbers[thousand] = "Thousand";
        numbers[million] = "Million", numbers[billion] = "Billion";
        string res;
        for (int k = 1000000000; k >= 100; k /= 1000)
        {
            if (num >= k)
            {
                res += ' ' + get3(num / k) + ' ' + numbers[k];
                num %= k;
            }
        }
        if (num) res += ' ' + get3(num);
        if (res.empty()) res = ' ' + numbers[0];
        return res.substr(1);
    }

    string get3(int num)
    {
        string res;
        if (num >= hundred)
        {
            res += ' ' + numbers[num / hundred] + ' ' + numbers[hundred];
            num %= hundred;
        }
        if (num)
        {
            if (num < 20) res += ' ' + numbers[num];
            else if (num % 10 == 0) res += ' ' + numbers[num];
            else res += ' ' + numbers[num / 10 * 10] + ' ' + numbers[num % 10];
        }
        return res.substr(1);
    }
};

Java代码

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
class Solution {
    public String numberToWords(int num) {
        if(num == 0){
            return "Zero";
        }
        String[] cardinal = {""," Thousand"," Million"," Billion"};
        List<String> list = new ArrayList<>();
        int count =0;
        StringBuffer english = new StringBuffer() ;
        while(num!=0){
            list.add(hundredNumber(num%1000));
            count ++;
            num = num / 1000;
        }
        while(count>0){
            english.append(list.get(count-1));
            if(!list.get(count-1).equals("")){
                english.append(cardinal[count-1]);
            }
            count --;
        }
        String col = english.toString();
        return col.substring(1);
    }
    
    public static String hundredNumber(int num) {
        String[] single = {" One"," Two"," Three",
                           " Four"," Five"," Six"," Seven",
                           " Eight"," Nine"};
        String[] tenToTwenty = {" Eleven"," Twelve",
                                " Thirteen"," Fourteen"," Fifteen",
                                " Sixteen"," Seventeen"," Eighteen"," Nineteen"};
        String[] tens = {" Ten"," Twenty"," Thirty"," Forty",
                         " Fifty"," Sixty"," Seventy",
                         " Eighty"," Ninety"};
        String hun = " Hundred";

        StringBuffer english = new StringBuffer() ;

        int a = num % 10; 
        int b = num % 100;
        int c = num % 1000;
        if(c!=b && c!=a) {
            english.append(single[c / 100-1]);
            english.append(hun);
        }

        if(b!=a){
            if(10 < b && b < 20){
                english.append(tenToTwenty[b%10-1]);
            }else {
                english.append(tens[b/10-1]);
            }
        }

        if(a != 0 ){
            if(!(10 < b && b < 20)){
                english.append(single[a-1]);
            }
        }
        return english.toString();
    }
}