Question

我一直试图输入正确的代码，以便从用户输入中找到最大数字和最小数字。到目前为止我的代码，我能够找到平均数，是否存在我可以使用运营商吗？：

package labs;

import java.util.Scanner;

public class Lab7method {

public static double readNumber(Scanner input, String prompt, String errorMessage, boolean toBePositive, boolean askForInteger) {
boolean hasError = true;    // assume to have error
double number = 0;  //initialize number


while (hasError) {
        // Prompt the user to input
        System.out.print(prompt);

        // Check if it is non-numeric data
        if (!input.hasNextDouble()) {   
            // If it is, report the error
            System.out.println(errorMessage);
            input.next();   // throw the input away by reading it
        } else if (askForInteger && !input.hasNextInt()) {
            // report the non-integer error
            System.out.println(errorMessage);
            input.next();   // throw the input away by reading it
        }
        else {
            // read the number
            number = input.nextDouble();

            // if the caller wants only positive number, check for negative or zero
            if (toBePositive && number <= 0)
                System.out.println(errorMessage); // report the error
            else
                // end the error checking loop
                hasError = false;
        }
    }

    // return the number to the caller
    return number;
}

// the really used method
public static int readInteger(Scanner input, String prompt, String errorMessage) {
    // invoke the readNumber() to an integer
    int anInteger = (int)readNumber(input, prompt, errorMessage, false, true);

    // return to the caller
    return anInteger;
}


// the really used method
public static double readDouble(Scanner input, String prompt, String errorMessage) {
    // invoke the readNumber() to do the actual work
    double aNumber = readNumber(input, prompt, errorMessage, false, false);

    // return to the caller
    return aNumber;
}

// the really used read positive double method
public static double readPositiveDouble(Scanner input, String prompt, String errorMessage) {
    // invoke the readNumber() to get a positive floating point number
    double aNumber = readNumber(input, prompt, errorMessage, true, false);

    // return to the caller
    return aNumber;
}

public static int readPositiveInt(Scanner input, String prompt, String errorMessage) {
    int anposInteger = (int) readNumber(input, prompt, errorMessage, true, false);
    return anposInteger;
}

public static void main(String[] args) {
    // Create a Scanner object
    Scanner input = new Scanner(System.in);

    //initial account balance//

    int noofgrades = readPositiveInt(input, "Enter number of grades: ", "Error you did not enter a positive integer:");
    double lowestGrade = 0;
    double highestGrade = 0;    
    double sumOfGrade = 0;
    double grade = 0;



    for (int i = 0; i < noofgrades; i++){           

        double Grade = 0;   
    // monthly interest rate//

    double mograde = readPositiveDouble(input, "Please enter grade " + (i +1) + ": ", "Errorrrrrrrr");


    sumOfGrade += mograde;
    }

    double averagegrade = sumOfGrade/noofgrades;

     // Do I use these -> Double.MAX_VALUE;
     // Do I use these -> Double.MIN_VALUE;     


        System.out.printf("The average of the grades entered are: %4.2f\n"
                            + "The highest grade: %4.2f\n" + "The lowest grade is: %4.2f\n" 
                            , averagegrade, highestGrade, lowestGrade);

Answer 1

您只需要在if for方法的main循环中添加几个for (int i = 0; i < noofgrades; i++) { double Grade = 0; // monthly interest rate// double mograde = readPositiveDouble(input, "Please enter grade " + (i + 1) + ": ", "Errorrrrrrrr"); if (i == 0) { lowestGrade = mograde; highestGrade = mograde; } else { if (mograde < lowestGrade) { lowestGrade = mograde; } if (mograde > highestGrade) { highestGrade = mograde; } } sumOfGrade += mograde; }语句，以找出最小值和最大值，例如：

[::-1]

Answer 2

尝试此示例，在输入后立即打印最小值：

   Scanner scanner = new Scanner(System.in);
    int n;
    int max = Integer.MIN_VALUE;
    int min = Integer.MAX_VALUE;

    while((n = scanner.nextInt()) != Integer.MIN_VALUE){
        max = n>max?n:max;
        min = n<min?n:min;
        System.out.println(String.format("Min: %d. Max %d", min, max));
    }

Answer 3

我跑了但是只有最高的数字才能打印出来。我输入的任何输入都是打印的最低数字0.00。

public static void main(String[] args) {
    // Create a Scanner object
    Scanner input = new Scanner(System.in);

    //initial account balance//

    int noofgrades = readPositiveInt(input, "Enter number of grades: ", "Error you did not enter a positive integer:");
    double lowestGrade = 0;
    double highestGrade = 0;    
    double sumOfGrade = 0;
    double grade = 0;



    for (int i = 0; i < noofgrades; i++){           



        double Grade = 0;   
    // monthly interest rate//

    double mograde = readPositiveDouble(input, "Please enter grade " + (i +1) + ": ", "Errorrrrrrrr");



    if(mograde < lowestGrade){
        lowestGrade = mograde;
    }


    if(mograde > highestGrade){
        highestGrade = mograde;
    }

    sumOfGrade += mograde;
    }

    double averagegrade = sumOfGrade/noofgrades;

     // Do I use these -> Double.MAX_VALUE;
     // Do I use these -> Double.MIN_VALUE;     


        System.out.printf("The average of the grades entered are: %4.2f\n"
                            + "The highest grade: %4.2f\n" + "The lowest grade is: %4.2f\n" 
                            , averagegrade, highestGrade, lowestGrade);                                                         






}

}

根据用户输入查找最大数量和最小数量（METHODS）

3 个答案: