codewars043: 庫存清單

Help the bookseller !

Solution:

import java.util.*;
public class StockList{
    public static String stockSummary(String[] lstOfArt, String[] lstOf1stLetter){
        if(lstOfArt == null || lstOfArt.length == 0){
            return "";
        }    
        Map<String,Integer> map = new HashMap<String,Integer>();
        for(String x : lstOfArt){
            String[] arr = x.split(" ");
            String c = x.substring(0,1);
            if(map.containsKey(c)){
                map.put(c,map.get(c) + Integer.valueOf(arr[1]));
            }else{
                map.put(c,Integer.valueOf(arr[1]));
            }    
        }
            StringBuilder sb = new StringBuilder();
            for(int i = 0; i < lstOf1stLetter.length; i++){
                Integer count = map.containsKey(lstOf1stLetter[i]) ? map.get(lstOf1stLetter[i]) : 0 ;
                if(i != lstOf1stLetter.length - 1){
                    sb.append(String.format("(%s : %d) - ",lstOf1stLetter[i],count));
                }else{
                    sb.append(String.format("(%s : %d)",lstOf1stLetter[i],count));
                }    
                 
            }    
           return sb.toString();
    }    
}

Example Test:

import static org.junit.Assert.*;
import org.junit.Test;
public class StockListTest{
    @Test
    public void test1(){
        String art[] = new String[]{"ABAR 200","CDXE 500","BKWR 250","BTSQ 890","DRTY 600"};
        assertEquals("(A : 200) - (B : 1140)", StockList.stockSummary(art, cd));
    
    }    
}