JAVA语法基础作业——动手动脑以及课后实验性问题 （五）

一、请编写程序将整数转换为汉字读法字符串

import java.util.Scanner;

public class Test {

public static void main(String[] args) {
    Scanner in=new Scanner(System.in);
    System.out.println("输入一个数：");
    double a;
    a=in.nextDouble();
    System.out.println(digitUppercase(a));
}
public static String digitUppercase(double n) { 
    String fraction[] = { "角", "分"}; 
    String digit[] = { "零", "壹", "贰", "叁", "肆", "伍", "陆", "柒", "捌", "玖"}; 
    String unit[][] = { { "元", "万", "亿"}, { "", "拾", "佰", "仟"}}; 

    String head = n < 0 ? "负" : ""; 
    n = Math.abs(n); 

    String s = ""; 
    for (int i = 0; i < fraction.length; i++) { 
        s += (digit[(int) (Math.floor(n * 10 * Math.pow(10, i)) % 10)] + fraction[i]).replaceAll("(零.)+", ""); 
    } 
    if (s.length() < 1) { 
        s = "整"; 
    } 
    int integerPart = (int) Math.floor(n); 

    for (int i = 0; i < unit[0].length && integerPart > 0; i++) { 
        String p = ""; 
    for (int j = 0; j < unit[1].length && n > 0; j++) { 
        p = digit[integerPart % 10] + unit[1][j] + p; 
        integerPart = integerPart / 10; 
        } 
    s = p.replaceAll("(零.)*零$", "").replaceAll("^$", "零") + unit[0][i] + s; 
    } 
    return head + s.replaceAll("(零.)*零元", "元").replaceFirst("(零.)+", "").replaceAll("(零.)+", "零").replaceAll("^整$", "零元整"); 
    } 

}

 程序截图：

二、数组表示大数

import java.util.Scanner;

public class Dashu {

public static void main(String[] args) {
    // TODO Auto-generated method stub
    String s1,s2;
    Scanner in=new Scanner(System.in);
    System.out.println("输入第一个大数：");
    s1=in.next();
    System.out.println("输入第二个大数：");
    s2=in.next();
    System.out.println(add(s1,s2));
    System.out.println(sub(s1,s2));

}

private static String add(String a, String b){ 
    System.out.print("加法:" + a+ "+" + b + "=");
    char[] aa = new StringBuffer(a).reverse().toString().toCharArray(); 
    char[] bb = new StringBuffer(b).reverse().toString().toCharArray(); 
    int aLen = aa.length; 
    int bLen = bb.length; 

    int len = aLen > bLen ? aLen : bLen; 

    int[] result = new int[len + 1]; 
    for (int i = 0; i < len + 1; ++i) { 
    int aint = i < aLen ? aa[i] - '0' : 0; 
    int bint = i < bLen ? bb[i] - '0' : 0; 
    result[i] = aint + bint; 
    } 

    for(int i=0;i<result.length-1;++i){ 
        if(result[i]>=10){
            result[i+1] += result[i]/10; 
            result[i] %= 10; 
            } 
    } 

    boolean flag = true; 
    StringBuffer sb = new StringBuffer(len); 
    for(int i=len;i>=0;--i){ 
        if(result[i]==0&&flag){ 
            continue; 
            }
        else{ 
            flag=false; 
            } 
        sb.append(result[i]); 
        } 
        return sb.toString(); 
        } 
    public static String sub(String f, String s){ 
        System.out.print("减法:" + f + "-" + s + "="); 
        // 将字符串翻转并转换成字符数组 
        char[] a = new StringBuffer(f).reverse().toString().toCharArray(); 
        char[] b = new StringBuffer(s).reverse().toString().toCharArray(); 
        int lenA = a.length; 
        int lenB = b.length; 
        int len = lenA > lenB ? lenA : lenB; 
        int[] result = new int[len];  
        char sign = '+';  
        if (lenA < lenB) { 
            sign = '-'; 
        } 
        else if (lenA == lenB){
            int i = lenA - 1; 
            while (i > 0 && a[i] == b[i]) { 
                i--; 
            } 
            if (a[i] < b[i]) { 
                sign = '-'; 
            } 
        } 
        for (int i = 0; i < len; i++) { 
            int aint = i < lenA ? (a[i] - '0') : 0; 
            int bint = i < lenB ? (b[i] - '0') : 0; 
            if (sign == '+') { 
                result[i] = aint - bint; 
            } 
            else { 
                result[i] = bint - aint; 
            } 
        } 
        for (int i = 0; i < result.length - 1; i++) { 
            if (result[i] < 0) { 
                result[i + 1] -= 1; 
                result[i] += 10; 
            } 
        } 

        StringBuffer sb = new StringBuffer(); 
        if (sign == '-') { 
            sb.append('-'); 
        }  
        boolean flag = true; 
        for (int i = len - 1; i >= 0; i--) { 
            if (result[i] == 0 && flag) { 
                continue; 
            } 
            else { 
                flag = false; 
            } 
            sb.append(result[i]); 
        } 
        if (sb.toString().equals("")) { 
            sb.append("0"); 
        } 
        System.out.println(sb.toString()); 
        return sb.toString(); 
    } 
}

程序截图：

三、随机生成10个数，填充一个数组，然后用消息框显示数组内容，接着计算数组元素的和，将结果也显示在消息框中

import javax.swing.JOptionPane;

public class Shuzu {

public static void main(String[] args) {
    // TODO Auto-generated method stub
    int a[],sum=0;
    a=new int[10];
    String output=new String();
    for(int i=0;i<a.length;i++){
        a[i]=(int)(Math.random()*100);
        }
    output+="a[10]={";
    for(int i=0;i<a.length;i++){
        output+=a[i]+" ";
        }
    output+="}";
    for(int i=0;i<a.length;i++){
        sum+=a[i];
        }
    output+="
sum:"+sum;
    JOptionPane.showMessageDialog(null, output,"结果",
    JOptionPane.PLAIN_MESSAGE);
    }
}

程序截图：

 

设计思想：

随机产生10个相加数求和。