Question

我正在尝试为家庭作业完成这个程序，这是唯一不起作用的东西。我在这一行得到了预期的错误：

的System.out.println（myChars.equals（补体））;

这是我的代码

public class WCpalindrome {
  private static char[] dna = {'A', 'C', 'T', 'G'};
  private static ArrayList<Character> myChars = new ArrayList<Character>();
  private static ArrayList<Character> reverse = new ArrayList<Character>();
  private static ArrayList<Character> complement = new ArrayList<Character>();


public static char toUpperCase(char c) {
  if (c == 'A' || c == 'a') {
    return 'A';
  } else if (c == 'T' || c == 't') {
    return 'T';
  } else if (c == 'C' || c == 'c') {
    return 'C';
  }
  return 'G';
}

public static char getComplement(char c) {
  if (c == 'A' || c == 'a') {
    return 'T';
  } else if (c == 'T' || c == 't') {
    return 'A';
  } else if (c == 'C' || c == 'c') {
    return 'G';
  }
  return 'C';
}

public static void main(String[] args) {

  char current;
  int i = 0;

  //Get the input sequence
  while (StdIn.hasNextChar()) {
    current = StdIn.readChar();
    current = toUpperCase(current);
    myChars.add(current);
    StdOut.println(myChars.get(i));
    i++;
  }

  System.out.println();

  //Reverse the sequence
  int k = 0;
  int size = myChars.size() - 1;
  for (int j = size-1; j >= 0; j--) {
    current = myChars.get(j);
    StdOut.println(current);
    reverse.add(k, current);
    k++;
  }

  System.out.println();

  //Complement the reversed sequence
  int n = 0;
  size = myChars.size() - 1;
  for (n = 0; n < size; n++) {
    current = reverse.get(n);
    complement.add(getComplement(current));
    StdOut.println(complement.get(n));
  }
}

//Prints true if the original equals the complement of the reversal
//else it prints false
System.out.println(myChars.equals(complement));

}

Answer 1

您正在谈论的线路不在任何方法内。我想你想在主方法中移动它。

Answer 2

您已将语句System.out.println(...);置于main()之外。将它向上移3行。它现在处于预期方法和字段声明的级别。

此外，equals将始终返回false，因为数组实例不会比较内部元素。 One might use Arrays.equals`但你可能只是使用：

System.out.println(new String(myChars).equals(new String(complement)));

Answer 3

System.out.println(myChars.equals(complement));

在主要方法之外。

这应该在最后

  }
//Prints true if the original equals the complement of the reversal
    //else it prints false
    System.out.println(myChars.equals(complement));
}
}

使用ArrayList <character> </character>时标识符无效

3 个答案: