Question

我在搜索数组中遇到问题; 以下是参数：该方法允许学生从他们现有的时间表中搜索课程名称。使用WHILE循环，当两个条件之一为真时将停止：要么找到课程，要么已到达计划中的最后一个课程并且没有匹配。如果找到课程，则打印出课程名称和学分数。如果找不到该课程，则打印出一条消息，说明该课程未列入学生的课程表。只搜索现有课程。如果数组未满，并且您搜索整个数组，则程序将出现运行时错误。

到目前为止，这是我的代码，提前谢谢你：

public class Student {
 //Instance Data
 String studentName;
 String studentID;
 String streetAddress;
 String city;
 String state;
 String zipCode;
 String major;

 int totalCredits;
 final int MAX_CREDITS = 18;
 final int SIZE = 6;
 String[] schedule = new String[SIZE];
 int courseNumber = 0;

 //Create Constructor:
 //Initializes the student data at instantiation time.
 //-------------------------------------------------------
 //  Sets up the student's information.
 //-------------------------------------------------------
 public Student(String name, String id, String address, String cityName, String stateName, String zip, String area) {
   studentName = name;
   studentID = id;
   streetAddress = address;
   city = cityName;
   state = stateName;
   zipCode = zip;
   major = area;
  } //end Student Constructor

 //Method to Return student information as string:
 //-------------------------------------------------------
 //  Returns the student information as a formatted string.
 //-------------------------------------------------------
 public String toString() {
   String studentInfo;

   studentInfo = "Name:\t\t\t" + studentName + "\n" + "ID:\t\t\t" + studentID + "\n" + "Address:\t\t" + streetAddress + "\n" + "City:\t\t\t" + city + "\n" + "State:\t\t\t" + state + "\n" + "Zip Code:\t\t" + zipCode + "\n" + "Major:\t\t\t" + major + "\n";

   return studentInfo;
  } // end toString


 //Method to determine if maximum allowed credits have been exceeded
 //-------------------------------------------------------
 //  Returns true if total credits does not exceed 18.
 //-------------------------------------------------------
 private boolean checkCredits(int numCredits) {
   if (numCredits + totalCredits <= MAX_CREDITS) //make sure max   credits not exceeded
   {
    return true; //return a true if still less than 18 credits
   } else {
    return false; //return a false if 18 credit limit is exceeded
   } //end numCredits
  } //checkCredits
  //Method to add a course to the student’s schedule
  //-------------------------------------------------------
  //  Adds a course to the array if total credits does not exceed 18.
  //-------------------------------------------------------
 public void addCourse(String course, int numCredits) {
   if (courseNumber < SIZE) //make sure array is not full. 
   {
    if (checkCredits(numCredits) == true) //if we’re under 18 credits
    {
     //add course
     schedule[courseNumber] = course + ":\t\t" + numCredits + "\tCredits\n";
     //increment number of credits
     totalCredits = totalCredits + numCredits;
     //increment number of courses
     courseNumber = courseNumber + 1;
    } else //oops – can’t do more than 18 credits
    {
     System.out.println("You have exceeded  the maximum allowed credits.");
    } //end checkCredits
   } else //oops – can’t do more than 10 courses
   {
    System.out.println("You have exceeded 10 courses.");
   } //end courseNumber
  } //addCourse
  //Method to display the schedule
  //-------------------------------------------------------
  //  Will only print out the courses added to the array.
  //-------------------------------------------------------
 public void displaySchedule() {
   for (int index = 0; index < courseNumber; index++) {
    System.out.println("Course #" + (index + 1) + " " + schedule[index] + "\n");
   } //end for

  } //end display schedule
 public void searchCourse(String courseName) {
  int index;
  String extract;
  boolean notFound = true;
  index = 0;
  while (index < SIZE) {
   extract = schedule(index).charAt(0, 6);
   if (courseName != extract) {
    index++;
   } else {
    notFound = false;
   }
   if (notFound = true) {
    System.out.println("Course Found");
   } else {
    System.out.println("Course Not Found");
   }
  }
 }
}

Answer 1

搜索方法看起来效率不高，可能是这样的：

while(index++ < SIZE){
    extract = schedule(index).charAt(0,6);
    if(!(extract == courseName)){ // i belive this returns 0 if true, which would make our if statement false, just use the not operator
        // found the course, do stuff
        return;
    }
}
// if loop ends, then we didn't find the course, do stuff

如何搜索阵列的课程

1 个答案: