public class Bank {
/**
* 變量和數(shù)據(jù)類型的用法之int類型
*/
public static void main(String[] args) {
int money = 1000;
System.out.println("劉老師在銀行的存款是：" + money);
}
}
基本數(shù)據(jù)類型的使用，double,String和char
public class Score {
/**
* @param args
*/
public static void main(String[] args) {
// 輸出最高分同學(xué)的信息
double maxScore = 99.5;
String name = "姚遠(yuǎn)";// ^_^
// String sex="男";也可以
char sex = '男';
System.out.println("最高分同學(xué)的信息是：");
System.out.println("得分：" + maxScore);
System.out.println("姓名：" + name);
System.out.println("性別是：" + sex);
}
}
這個(gè)類的一部分演示了數(shù)學(xué)運(yùn)算
double r;
Scanner s = new Scanner(System.in);
System.out.println("請(qǐng)輸入半徑：");
r = s.nextInt();
double area = r * r * 3.14;
System.out.println(area);
這是一個(gè)復(fù)雜一點(diǎn)的例子，計(jì)算加減乘除
import java.util.Scanner;
public class jisuan {
/**
* 輸入兩個(gè)數(shù)尚揣，計(jì)算它們的加減乘除的結(jié)果
*/
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
System.out.println("請(qǐng)輸入兩個(gè)整數(shù):");
int zs1 = input.nextInt();
int zs2 = input.nextInt();
int j = zs1 + zs2;
int jian = zs1 - zs2;
int c = zs1 * zs2;
double chu = (double) zs1 / zs2;
System.out.println("這兩個(gè)數(shù)字加減乘除的結(jié)果分別是:" + j + "\n" + jian + "\n" + c
+ "\n" + chu);
}
}
public class Operator {
/**
* 運(yùn)算符的使用站玄，演示了++和%的用法，注意，部分語言不支持浮點(diǎn)類型的余運(yùn)算
*/
public static void main(String[] args) {
int a = 10, b = 6;
a++;
System.out.println("a=" + a);
double d = 11.7;
d++;
System.out.println(d);
int c = a / b;
System.out.println(c);// 為什么是1
int y = a % b;
System.out.println(a + "%" + b + "=" + y);
double d2 = 5.3;
double d3 = d % d2;
System.out.println(d3);
}
}
public class Score {
/**
* @param args
*/
public static void main(String[] args) {
// 輸出最高分同學(xué)的信息
double maxScore = 99.5;
String name = "姚遠(yuǎn)";// ^_^
// String sex="男";也可以
char sex = '男';
System.out.println("最高分同學(xué)的信息是：");
System.out.println("得分：" + maxScore);
System.out.println("姓名：" + name);
System.out.println("性別是：" + sex);
}
}
如下的例子演示了基本數(shù)據(jù)類型的賦值：直接拷貝
public class Score1 {
public static void main(String[] args) {
int zhanghaoScore = 80;
int wangScore = zhanghaoScore;
zhanghaoScore = 91;
System.out.println("王蒙的成績是：" + wangScore);
}
}
char其實(shí)是數(shù)字
public class Zhuanhuan {
/**
* 演示了char,其實(shí)是數(shù)字
*/
public static void main(String[] args) {
char s = '劉';
int i = s;
int j = '張';
System.out.println(i);
System.out.println(j);
}
}
數(shù)據(jù)類型的轉(zhuǎn)換纫谅，損失的不光是小數(shù)點(diǎn)
public class Zhuanhuang2 {
/**
*
* 如果一個(gè)數(shù)字沒有小數(shù)點(diǎn)炫贤，其實(shí)他是int，想變成double,后面加上字母d
*/
public static void main(String[] args) {
double a = 9.8;
double b = 7.6;
int now = (int) (a + b);// 類型強(qiáng)轉(zhuǎn)
System.out.println(now);
double c = 393993339393939393d;
int i = (int) c;
System.out.println(i);
}
}
