Problem Description
Conversion between the metric and English measurement systems is relatively simple. Often, it involves either multiplying or dividing by a constant. You must write a program that converts between the following units:

Input
The first line of input contains a single integer N, (1 ≤ N ≤ 1000) which is the number of datasets that follow.
Each dataset consists of a single line of input containing a floating point (double precision) number, a space and the unit specification for the measurement to be converted. The unit specification is one of kg, lb, l, or g referring to kilograms, pounds, liters and gallons respectively.

Output
For each dataset, you should generate one line of output with the following values: The dataset number as a decimal integer (start counting at one), a space, and the appropriately converted value rounded to 4 decimal places, a space and the unit specification for the converted value.

Sample Input
5
1 kg
2 l
7 lb
3.5 g
0 l

Sample Output
1 2.2046 lb
2 0.5284 g
3 3.1752 kg
4 13.2489 l
5 0.0000 g

题目很简单，就是给出了汇率，让你转换！！！
水题！

import java.util.Scanner;

public class Main{
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String[] str1 = {
  
  
  "kg","l","lb","g"};
        String[] str2 = {
  
  
  "lb","g","kg","l"};
        double[]  d = {
  
  
  2.2046,0.2642,0.4536,3.7854};
        int time = 1;
        int t = sc.nextInt();
        while(t-->0){
            int k=0;
            double n = sc.nextDouble();
            String s = sc.next();
            for(int i=0;i<str1.length;i++){
                if(s.equals(str1[i])){
                    k=i;
                    n = n*d[i];
                    break;
                }
            }
            System.out.printf("%d %.4f %s",time,n,str2[k] );
            System.out.println();
            time++;
        }


    }

}

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