如何获取以分数的“分子/分母”形式返回分数的字符串版本的方法

Question

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package fractioncal;

import static java.lang.Integer.sum;
import java.util.Scanner;

/**
 *
 * @author abdallah
 */
public class FractionCal {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
        System.out.println("Fraction Calculator");
        System.out.println("Enter first fraction");
        String firstfraction = s.nextLine();
        System.out.println("Enter second fraction");
        String secondfraction = s.nextLine();
        System.out.println("Processing "+firstfraction+","+secondfraction);

        String frac0 = firstfraction.substring(0,1);
        String frac1 = firstfraction.substring(2,3);

        int numerator1 = Integer.parseInt(frac0);
        int denominator1 = Integer.parseInt(frac1);

        String frac2 = secondfraction.substring(0,1);
        String frac3 = secondfraction.substring(2,3);
        int numerator2 = Integer.parseInt(frac2);
        int denominator2 = Integer.parseInt(frac3);
        int sum = getAdd(numerator1, numerator2,denominator1,denominator2,firstfraction);

        System.out.println("Sum ="+sum);

    }
    public static int getAdd(int numerator1, int numerator2,int denominator1, int denominator2,String firstfraction ){

        int numer = (numerator1 * denominator2) + (denominator1 * numerator2);
        int deno = (denominator1*denominator2);                 

        return sum(numer,deno);
    }   
}

Answer 1

Your getAdd() method should be like this:

public static String getAdd(int numerator1, int numerator2, int denominator1, int denominator2) {

    int numer = (numerator1 * denominator2) + (denominator1 * numerator2);
    int deno = (denominator1 * denominator2);

    return numer + "/" + deno;
}

For input:

1/3 and 2/4

Output:

Sum =10/12