Lessons Learned and fifth week experiment report

Course Summary: Learn about common methods String class and learned a lot about some applications Stirng class of problems in the process of doing.

1. Known string: "this is a test of java" required to do the following requirements :( source code, the results screenshot).

• The number of letters in the string s occurs statistics.
• The string neutron count the number of times the string "is" appears.
• The number of words in the string "is" appears in the statistics.
• Achieve reverse the string is output.

package twst;

public class test {
 public static void main(String args[]) {
  String str="this is a test of java";
  int x=(str.split("s")).length-1;
  System.out.println("s出现的次数="+x);
  int n=(str.split("is")).length-1;
  System.out.println("is出现的次数="+n);
  char s='s',i='i';
  char c[]=str.toCharArray();
  int count=0;
  for(int j=0;j<c.length;j++) {
   if(' '==c[j] && i==c[j+1] && s==c[j+2] && ' '==c[j+3]) {
    count++;
   }
  }
  System.out.println("单词is出现的次数="+count);
  for(int a=c.length-1;a>=0;a--) {
   System.out.print(c[a]);
  }
 }
}

 

 2. Write a program, using the following algorithm to encrypt or decrypt the English string input by the user. It requires source code, the results screenshot.

package twst;

public class jiami {
    public String jiami(String s1){ 
        int i,j; 
        String allstring="ABCDEFGABC"; 
        StringBuffer ss = new StringBuffer();
        for(j=0;j<s1.length();j++) { 
            char s2=s1.charAt(j);
            for(i=0;i<allstring.length()-3;i++){ 
                char allstring1=allstring.charAt(i); 
                char allstring2=allstring.charAt(i+3); 
                if(allstring1==s2) {
                    ss.append(allstring2);
                    break;
                }
            } 
        } 
        String s3 = ss.toString();
        return s3; 
    } 
} 


package twst;

public class password {
    public static void main(String[] args){ 
        jiami newpassword=new jiami(); 
        String str="ABCDEFH";
        System.out.print(newpassword.jiami(str)); 
    } 
}

 

 

 

 

 

Question: This question can not write, I'm still a little not write.

 3. Given the string "ddejidsEFALDFfnef2357 3ed". The output string in the number of capital letters, lowercase letters count, the number of non-English letters.

package twst;

public class test {
    public static void main(String args[]) {
        String str="ddejidsEFALDFfnef2357 3ed";
        char c[]=str.toCharArray();
        for(int i=0;i<c.length;i++) {
            if(c[i]>='A'&&c[i]<='Z') {
                System.out.println("大写英文字母="+c[i]);
            }
            else if(c[i]>='a'&&c[i]<='z') {
                System.out.println("小写英文字母="+c[i]);
            }
            the else { 
                System.out.println ( "other characters =" + C [I]); 
            } 
        } 
        
    } 
}