课堂作业练习题
1.显示三条信息
package Ch01;
public class Ex01_01 {
public static void main (String [] args){
System.out.println("Welcome to Java");
System.out.println("Welcome to Computer Science");
System.out.println("Programming is fun");
}
}
2.显示五条信息Welcome to java
package Ch01;
public class EX01_02 {
public static void main (String [] args){
System.out.println("Welcome to java");
System.out.println("Welcome to java");
System.out.println("Welcome to java");
System.out.println("Welcome to java");
System.out.println("Welcome to java");
}
}
3.编写java图案
package Ch01;
public class Ex01_03 {
public static void main (String []args){
System.out.println(" J A V V A");
System.out.println(" J A A V V A A");
System.out.println(" J J AAAAA V V AAAAA");
System.out.println(" JJ A A V A A");
}
}
4.打印表格
package Ch01;
public class Ex01_04 {
public static void main(String [] args)
{
System.out.println("a a^2 a^3");
System.out.println("1 1 1");
System.out.println("2 4 8");
System.out.println("3 9 27");
System.out.println("4 16 64");
}
}
5.编写程序表示（计算表达式），显示以下式子的结果
public class Ex01_05 {
public static void main (String []args)
{
double a;
double b;
double c;
double d;
//Declare a b c d为实数，也称浮点数）
a = 9.5; b = 4.5; c = 2.5; d = 3.5;
double outcome1; double outcome2; double outcome;
outcome1 = a * b - c * 3;
outcome2 = 45.5 - d;
outcome = outcome1/outcome2;
System.out.println("The answer is" + outcome);
/*其实没有必要赋值a，b，c，d可直接通过outcome1=9.5*4.5-2.5*3...实现
但是想练习用double表明浮点数以及记住每个命令后都需要；结尾，因此选择这样多练习了几次
应该算是有损计算机性能的方法，不过不管怎么说都出结果了
*/
}
}
计算归计算，结果还是需要用System.out.println("")表示出，才会在控制台中显示*
6.编写程序数列求和
package Ch01;
public class Ex01_06 {
public static void main(String[] args) {
double outcome ;
outcome= 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9;
System.out.println("The answer is " + outcome);
}
}