Lab8


4531201521_4531202121  นาย เกรียงยุทธ หวังจิตมั่น และ นาย กฤษฎา เฉลิมสุข (3/9/2545 (11:46:50))
(SM=3, CM=15, ST=7, KY=0, TR=04:30)

TestScript
Mini-Quiz :  (0.0 คะแนน)

JLab>java Selftest
>>JLabIO->recripocate : ok
>>JLabIO->recripocate : ok
>>JLabIO->multiply : ok
>>JLabIO->multiply : ok
>>JLabIO->multiply : ok
>>JLabIO->multiply : ok
>>JLabIO->addMatrix : ok
>>JLabIO->addMatrix : ok

>>JLab:<POINT>8</POINT>
JLab>

ได้ 8 คะแนน
Source Code
// 2110101 : Lab8 (2545)
// dept. of computer engineering
// Chulalongkorn Univ.

import jlab.JLabIO;

public class Rational {
  int numerator;
  int denominator;

  //--------------------------------------------------------
  // an object method returning the recripocal of "this"
  // rational number.
  public Rational recripocate() {

    Rational x = new Rational(this.denominator, this.numerator);
    return x;
    
  }
  //--------------------------------------------------------
  // an object method returning the result of "this"
  // rational number multiplied by a.
  public Rational multiply(Rational a) {

    Rational x, y, z;
    x = new Rational(this.numerator, a.denominator);
    y = new Rational(a.numerator, this.denominator);
    z = new Rational(x.numerator * y.numerator, y.denominator * x.denominator);
    return z;

  }
  //--------------------------------------------------------
  // a class method for multiplying two matrices of rational
  // numbers (matrices a and b).
  public static Rational[][] mulMatrix(Rational[][] a, Rational[][] b) {

    Rational[][] mul = new Rational[a.length][b[0].length];
    int n = a.length;
    int m = b[0].length;
    for (int i = 0; i < n; i++) {
      for (int j = 0; j < m; j++) {
        Rational sum =new Rational();
         for (int k = 0; k < m; k++) {
        Rational x = a[i][k].multiply(b[k][j]);
        sum = sum.add(x);}
        mul[i][j] = sum;
      }
      
    }
    return mul;
  }
  //--------------------------------------------------------
  // you can use the main method for your own testing (optional).
  public static void main(String[] args) {
    



  }
  //--------------------------------------------------------
  public Rational() {
    this(0, 1);
  }
  public Rational(int n, int d) {
    int g = gcd(n, d);
    n = n / g;
    d = d / g;
    this.numerator = n;
    this.denominator = d;
  }
  public Rational add(Rational a) {
    int g = gcd(this.denominator, a.denominator);
    int d = this.denominator / g * a.denominator;
    int n = this.numerator * d / this.denominator +
            a.numerator * d / a.denominator;
    return new Rational(n, d);
  }
  public String toString() {
    return this.numerator + "/" + this.denominator;
  }
  public static int gcd(int a, int b) {
    return b == 0 ? a : gcd(b, a % b);
  }
}