java上机第三周 任务3 分数的四则运算

/* * 程序头部注释开始   * 程序的版权和版本声明部分   * Copyright (c) 2011, 烟台大学计算机学院学生   * All rights reserved.   * 文件名称：分数的四则运算                               * 作    者：薛广晨                               * 完成日期：2011  年 09 月  13  日   * 版 本号：x1.0               * 对任务及求解方法的描述部分   * 输入描述：  * 问题描述:  实现分数的四则运算，即两个分数相减，相乘和相除  * 程序输出：   * 程序头部的注释结束 */package xue.com;public class TestFractory1 {/** * @param args */public static void main(String[] args) {// TODO Auto-generated method stubfracAdd(1,5,7,20);//结果为：11/20fracSub(1,5,7,20);//分数相减fracMul(1,5,7,20);//分数相乘fractDiv(1,5,7,20);//分数相除}private static void fractDiv(int first_numrator,int first_denominator,int second_numrator,int second_denominator) {// TODO Auto-generated method stubint third_numrator = first_numrator * second_denominator;int third_denominator = first_denominator * second_numrator;int j = gcd(third_numrator, third_denominator);third_numrator = third_numrator / j;third_denominator = third_denominator /j;System.out.println(first_numrator + "/" + first_denominator + " ÷ " + second_numrator + "/" + second_denominator + " = " + third_numrator + "/" + third_denominator);}private static void fracMul(int first_numrator,int first_denominator,int second_numrator,int second_denominator) {// TODO Auto-generated method stubint third_numrator = first_numrator * second_numrator;int third_denominator = first_denominator * second_denominator;int j = gcd(third_numrator, third_denominator);third_numrator = third_numrator / j;third_denominator = third_denominator /j;System.out.println(first_numrator + "/" + first_denominator + " X " + second_numrator + "/" + second_denominator + " = " + third_numrator + "/" + third_denominator);}private static void fracSub(int first_numrator,int first_denominator,int second_numrator,int second_denominator) {// TODO Auto-generated method stubint i = lcm(first_denominator, second_denominator);int third_numrator = (i / first_denominator) * first_numrator - (i / second_denominator) * second_numrator;int j = gcd(third_numrator, i);third_numrator = third_numrator / j;int third_denominator = i /j;System.out.println(first_numrator + "/" + first_denominator + " - " + second_numrator + "/" + second_denominator + " = " + third_numrator + "/" + third_denominator);}static void fracAdd(int first_numrator,int first_denominator,int second_numrator,int second_denominator){//以下代码能够在控制台上显示结果//需要调用求最大公约数的函数//需要调用求最小公倍数的函数int i = lcm(first_denominator, second_denominator);int third_numrator = (i / first_denominator) * first_numrator + (i / second_denominator) * second_numrator;int j = gcd(third_numrator, i);third_numrator = third_numrator / j;int third_denominator = i /j;System.out.println(first_numrator + "/" + first_denominator + " + " + second_numrator + "/" + second_denominator + " = " + third_numrator + "/" + third_denominator);}static int gcd(int m,int n){int i = 2;//定义循环控制变量     int gc = 1;//求最大公约数   int min = m < n ? m : n;   while (i <= min)    {    while (m % i == 0 && n % i == 0)//求分子分母共同的公约数         {    m = m / i;            n = n / i;            min = m < n ? m : n;            gc = gc * i;        }        ++i;    }    return gc;    }static int lcm(int m,int n){int gc = gcd(m, n);//求最大公约数     int lc = (m / gc) * (n / gc) * gc;//最小公倍数与最大公约数有一定关系     return lc;  }}

 

 

运行结果：

1/5 + 7/20 = 11/20
1/5 - 7/20 = -3/20
1/5 X 7/20 = 7/100
1/5 ÷ 7/20 = 4/7