Question

我想找出给定实数有多少除数并想要打印这些除数。但是我得到错误：输入正整数：25

25的除数是1 除数是1

25的除数是2 除数是2

25的除数是3 除数是3

一遍又一遍地打印。程序工作正常，并告诉该数字有多少除数。但是当我试图打印出这些数字并显示它们时，问题。是否需要一个数组？有一个伟大的头脑那里帮助我解决这个问题？不是家庭作业

这是我的源代码

public class CountDivisors {
public static void main(String[] args) {
int N; // A positive integer entered by the user.
// Divisors of this number will be counted.
int testDivisor; // A number between 1 and N that is a
// possible divisor of N.
int divisorCount; // Number of divisors of N that have been found.
int numberTested; // Used to count how many possible divisors
int positiveDivisor;
// of N have been tested. When the number
// reaches 1000000, a period is output and
// the value of numberTested is reset to zero.
/* Get a positive integer from the user. */
while (true) {
System.out.print("Enter a positive integer: ");
N = TextIO.getlnInt();
if (N > 0)
break;
System.out.println("That number is not positive. Please try again.");
}
/* Count the divisors, printing a "." after every 1000000 tests. */
divisorCount = 0;
numberTested = 0;
positiveDivisor=0;
for (testDivisor = 1; testDivisor <= N; testDivisor++) {

if ( N % testDivisor == 0 )
{
positiveDivisor++;
divisorCount++;
numberTested++;
if (numberTested == 1000000) {
System.out.println("Whoof!! Just tested a Million Numbers!!");
System.out.println("No probs.LETS GO AGAIN!!");
numberTested = 0;
}
}
/* Display the result. */
System.out.println();
System.out.println("The number of divisors of " + N
+ " is " + divisorCount);
System.out.println("And the divisors are" + positiveDivisor);
} // end main()
} // end class CountDivisors
}

Answer 1

我在您的代码中发现了一些问题，首先我添加了Scanner因为我没有TextIO课程。接下来，我添加了一个List来存储除数（因为你只保留了一个计数）。所以，它应该看起来像 -

public static void main(String[] args) {
    Scanner scanner = new Scanner(System.in);
    int testDivisor;
    int numberTested; // Used to count how many possible divisors
    int N = -1;
    while (true) {
        System.out.print("Enter a positive integer: ");
        N = scanner.nextInt();
        if (N > 0) {
            break;
        }
        System.out.println("That number is not positive. Please try again.");
    }
    /* Count the divisors, printing a "." after every 1000000 tests. */
    numberTested = 0;
    List<Integer> divisors = new ArrayList<Integer>();
    for (testDivisor = 1; testDivisor <= N; testDivisor++) {
        if (N % testDivisor == 0) {
            divisors.add(testDivisor);
            numberTested++;
            if (numberTested == 1000000) {
                System.out.println("Whoof!! Just tested a Million Numbers!!");
                System.out.println("No probs.LETS GO AGAIN!!");
                numberTested = 0;
            }
        }
        /* Display the result. */
        System.out.println();
        System.out.println("The number of divisors of " + N + " is "
                + divisors.size());
        System.out.println("And the divisors are" + divisors);
    }
} // end main()

当我用25测试时，我确实得到了（不包括中间步骤） -

The number of divisors of 25 is 3
And the divisors are[1, 5, 25]

Answer 2

你的＆＃39; for＆＃39;循环是打印语句＆＃34; N的除数是＆＃34;多次。尝试将所有除数存储在ArrayList中，并在for循环之后放置另一个除数＆＃39; for＆＃39;循环打印那些。

.
.
.
ArrayList<int> divisor_array = new ArrayList<int>();
for (testDivisor = 1; testDivisor <= N; testDivisor++) {

  if ( N % testDivisor == 0 ) {
    positiveDivisor++;
    divisorCount++;
    numberTested++;
    divisor_array.add(testDivisor);

    if (numberTested == 1000000) {
      System.out.println("Whoof!! Just tested a Million Numbers!!");
      System.out.println("No probs.LETS GO AGAIN!!");
      numberTested = 0;
    }
  }
} //end the for loop here

/* Display the result. */
System.out.println();
System.out.println("The number of divisors of " + N + " is " + divisorCount);

//print all divisors
System.out.println("And the divisors are:");
for(int k : divisor_array) {
   System.out.println(k);
}

如何单独打印除数？

2 个答案: