练习2-1
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练习2-2
package candle1220;
class Nightwatch{
public static void main(String[] args) {
int x,y,z;
x=22;
y=23;
z=35;
System.out .println("合计值是"+(x+y+z)+"平均值是"+(x+y+z)/3);
}
}
练习2-3
package candle1220;
import java.util.Scanner;
class Nightwatch{
public static void main(String[] args) {
Scanner stdIn=new Scanner(System .in);
int x;
System .out .print("整数值:");
x=stdIn.nextInt();
System.out .println("输入的值是"+x);
}
}
练习2-4
package candle1220;
import java.util.Scanner;
class Nightwatch{
public static void main(String[] args) {
Scanner stdIn=new Scanner(System .in);
int x;
System.out.print("整数值:");
x=stdIn.nextInt();
System.out.println("加上10的值是"+(x+10));
System.out.println("减去10的值是"+(x-10));
}
}
练习2-5
package candle1220;
import java.util.Scanner;
class Nightwatch{
public static void main(String[] args) {
Scanner stdIn=new Scanner(System .in);
double x,y;
System.out.print("x的值:");
x=stdIn.nextDouble();
System.out.print("y的值:");
y=stdIn.nextDouble();
System.out.println("合计值是"+(x+y));
System.out.println("平均值是"+(x-y)/2);
}
}
练习2-6
package candle1220;
import java.util.Scanner;
class Nightwatch{
public static void main(String[] args) {
Scanner stdIn=new Scanner(System .in);
double x,y;
System.out.println("求三角形的面积。");
System.out.print("底:");
x=stdIn.nextDouble();
System.out.print("高:");
y=stdIn.nextDouble();
System.out.println("面积是"+(x*y)/2);
}
}
练习2-7
package candle1220;
import java.util.Scanner;
import java.util.Random;
class Nightwatch{
public static void main(String[] args) {
Scanner stdIn=new Scanner(System .in);
Random rand=new Random();
int lucky=rand.nextInt(9);
System.out.print("随机数:"+(lucky+1));
}
}
package candle1220;
import java.util.Scanner;
import java.util.Random;
class Nightwatch{
public static void main(String[] args) {
Scanner stdIn=new Scanner(System .in);
Random rand=new Random();
int lucky=rand.nextInt(9);
System.out.print("随机数:"+(lucky-9));
}
}
练习2-8
package candle1220;
import java.util.Scanner;
import java.util.Random;
class Nightwatch{
public static void main(String[] args) {
Scanner stdIn=new Scanner(System .in);
Random rand=new Random();
int lucky=(rand.nextInt(11)-5);
System.out.print("整数值:");
int x=stdIn.nextInt();
System.out.println("生成了该值±5范围内的随机数,是"+(x+lucky));
}
}
练习2-9
package candle1220;
import java.util.Scanner;
import java.util.Random;
class Nightwatch{
public static void main(String[] args) {
Scanner stdIn=new Scanner(System.in);
Random rand=new Random();
double lucky=rand.nextDouble();
System.out.print("随机数:"+lucky);
}
}
package candle1220;
import java.util.Scanner;
import java.util.Random;
class Nightwatch{
public static void main(String[] args) {
Scanner stdIn=new Scanner(System.in);
Random rand=new Random();
double lucky=10*rand.nextDouble();
System.out.print("随机数:"+lucky);
}
}
package candle1220;
import java.util.Scanner;
import java.util.Random;
class Nightwatch{
public static void main(String[] args) {
Scanner stdIn=new Scanner(System.in);
Random rand=new Random();
double lucky=(2*rand.nextDouble()-1);
System.out.print("随机数:"+lucky);
}
}
练习2-10
package candle1220;
import java.util.Scanner;
class Nightwatch{
public static void main(String[] args) {
Scanner stdIn=new Scanner(System.in);
String s1="柴田";
String s2="望洋";
System.out.println("姓:"+s1);
System.out.println("名:"+s2);
System.out.println("你好"+s2+s1+"先生。");
}
}
来源:oschina
链接:https://my.oschina.net/u/4410144/blog/4275686