2020.10.19日作业
第一题
package com.hp.www; public class Demo2 { public static void main(String[] args) { String s = "Hello-World"; System.out.println("是否相等,-"+s.equals("World")); System.out.println("Wo起始索引:"+s.indexOf("Wo")); System.out.println("3好索引"+s.charAt(3)); System.out.println("长度"+s.length()); System.out.println("获得s中的Hell字符串:"+s.valueOf("Hell")); System.out.println("获得s中的orld字符串:"+s.valueOf("orld")); System.out.println("将字符串s中的所有o替换成*号."+s.replace("o","*")); System.out.println("将字符串s切割Hell和World两个字符串."+s.replace(s,"Hello")); char []chars = s.toCharArray(); for(char a:chars ){ System.out.print(a+","); } } }
第二题
package com.hp.www; import java.util.Scanner; public class Demo3 { public static void main(String[] args) { Scanner scanner=new Scanner(System.in); String s= scanner.next(); char[] c=s.toCharArray(); int smallCount=0; int bigCount=0; int numCount=0; for (int i = 0; i <s.length() ; i++) { if (Character.isUpperCase(c[i])) { bigCount++; } else if (Character.isLowerCase(c[i])) { smallCount++; }else if (Character.isDigit(c[i])) { numCount++; } } System.out.println("大写字母数量为:"+bigCount); System.out.println("小写字母数量为:"+smallCount); System.out.println("数字数量为:"+numCount); } }
第三题
package com.hp.www; import java.util.Scanner; public class Demo4 { public static void main(String[] args) { Scanner scanner=new Scanner(System.in); System.out.println("键盘录入5个字符串"); String[]arr=new String[5]; for (int i = 0; i <5 ; i++) { String s= scanner.next(); arr[i]=s; } int smallCount=0; int bigCount=0; int numCoun=0; for (int i = 0; i <arr.length ; i++) { char[]c =arr[i].toCharArray(); for (int j = 0; j <c.length ; j++) { if(Character.isLowerCase(c[i])){ bigCount++; } else if (Character.isLowerCase(c[i])){ smallCount++; }else if(Character.isDigit(c[i])){ numCoun++; } } } System.out.println("大写字母数量为:"+bigCount); System.out.println("小写字母数量为:"+smallCount); System.out.println("数字数量为:"+numCoun); } }