java - 在java中获取0作为数组的总和

Question

当我测试我的代码时，我不断得到 0 作为以下代码的总和和平均值，但它可以编译。我不确定我做错了什么。

public class Array {
  int array[];
  int sum;

  Array(int[] array) {
    this.array = new int[10];

  }
  public int sum(){
      for (int i = 0; i < array.length - 1; i++)
         sum += sum + array[i];
      return sum;
    }
  public double average() {
      for (int i = 0; i < array.length - 1; i++)
         sum += sum + array[i];
      int average = sum / array.length;
      return average;
  }
}

Answer 1

   Array(int[] array) {
     this.array = new int[10];      //The Problem is here

   }

用这个

   Array(int[] array) {
      this.array = array;

   }

并将总和更改为

  sum = sum + array[i];

  or

  sum += array[i];

Answer 2

问题：

• 您所写的数组仅包含零。
• 你sum += sum + array[i];的不对。要么使用，要么+=在右边有总和并使用=，但不能同时使用。
• 您的平均值应该将分子或分母转换为双倍，因此您进行双除法而不是整数除法。

Answer 3

在这里你有一些错误......

public class Array {
    int array[];
    int sum;

    Array(int[] array) {
        this.array = new int[10];
        // this is write but wrong because if you are getting array of int as an argument then why you are not using it. here you can write like this
       // this.array = array;
    }
    public int sum(){
        for (int i = 0; i < array.length - 1; i++)
            sum += sum + array[i];
            // what is this? completely wrong logic for adding here you can use like this 
            // sum += array[i]   or you can use
            // sum = sum + array[i]
            return sum;
    }
    public double average() {
        for (int i = 0; i < array.length - 1; i++)
            sum += sum + array[i];
            // same mistake again
            // one more point is if you have called sum() function then sum(variable) is already having adding of arrays that time you can not summing up again

            int average = sum / array.length;
            return average;
     }
}

Answer 4

sum += sum + array[i]

应该 ：

sum += array[i];

在 for 循环中，您不会从长度中减去 1，因为您从索引 0 开始

它应该是 ：

for (int i = 0; i < array.length; i++) {
     // additional logic
}

Answer 5

1.改变

Array(int[] array) {
this.array = new int[10];
}

至

Array(int[] array) {
  this.array = array;
}

2.改变

 sum += sum + array[i];

至

sum += array[i];

3.改变

for (int i = 0; i < array.length - 1; i++)

至

for (int i = 0; i < array.length; i++)