3.12第二次作业
1.编写一个程序,定义圆的半径,求圆的面积.
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package Homework; import java.util.Scanner; public class A3 { public static void main(String[] args) { Scanner s = new Scanner(System.in); System.out.print( "输入圆的半径: " ); double r = s.nextDouble(); double ss = 3.14 * r * r; System.out.println( "圆的面积是: " + ss); } } |
2.华氏温度和摄氏温度互相转换
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package Homework; import java.util.Scanner; //摄氏度华氏度转换 public class A2 { public static void main(String[] args) { System.out.println( "选择你要转换的温度:" ); System.out.print( "摄氏度" + "\t" + "华氏度" ); Scanner s = new Scanner(System.in); String x = s.next(); if ( "摄氏度" .equals(x)) { System.out.println( "输入华氏度: " ); Scanner a = new Scanner(System.in); double h = a.nextDouble(); System.out.println( "摄氏度: " + (h - 32.00 ) * 5.00 / 9.00 ); } if ( "华氏度" .equals(x)) { System.out.println( "输入摄氏度: " ); Scanner b = new Scanner(System.in); double ss = b.nextDouble(); System.out.println( "华氏度: " + (((ss * 9.00 )/ 5.00 + 32.00 ))); } } } |
3.已知a,b均是整型变量,写出将a,b两个变量中的值互换的程序。
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package Homework; public class A4 { public static void main(String[] args) { int a = 5 ; int b = 8 ; System.out.println(a + "\t" + b); int x= a; a = b; b = x; System.out.println(a + "\t" + b); } } |
4.定义一个任意的5位整数,将它保留到百位,无需四舍五入
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package Homework; import java.util.Scanner; public class A5 { public static void main(String[] args) { Scanner s = new Scanner(System.in); System.out.print( "输入五位整数: " ); int x = s.nextInt(); int w = x / 100 * 100 ; System.out.println( "精确到百位: " + w); } } |
5.输入一个0~1000的整数,求各位数的和
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package Homework; import java.util.Scanner; //输入数字求各位数的和 public class A1 { public static void main(String[] args) { Scanner s = new Scanner(System.in); System.out.println( "请输入数字: " ); int x = s.nextInt(); if (x> 1000 || x< 0 ) { System.out.println( "输入数字不合法" ); return ; } else if (x/ 1000 == 1 ) { System.out.println( "数字和是:1" ); return ; } else if (x/ 100 != 0 ) { System.out.println( "数字的和是: " + (x/ 100 +x% 100 / 10 +x% 10 )); return ; } else if (x/ 10 != 0 ) { System.out.println( "数字的和是: " + (x/ 10 + x% 10 )); return ; } else { System.out.println( "数字的和是: " + x); } } } |
6.定义一个任意的大写字母A~Z,转换为小写字母
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package Homework; public class A6 { public static void main(String[] args) { String str1 = "A" ; String str2 = "a" ; String str11 = str1.toLowerCase(); String str22 = str2.toUpperCase(); System.out.println(str1 + ": " + str11); System.out.println(str2 + ": " + str22); } } |