一个java控制台程序，使用for循环[duplicate]将“BINARY”转换为“DECIMAL”，而不使用预定义的方法

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A java console program that converts decimal to binary without using a predefined method (for) 2 answers

一个java控制台程序,它将十进制转换为二进制,而不使用预定义的方法(for)2个答案

I made a java console program that prints the decimal value of the binary value inputted. Now, I have a problem with my program that

我制作了一个java控制台程序,它打印输入的二进制值的十进制值。现在,我的程序存在问题

for e.g. output: Enter input = 10011101 then the binary value is 3534200 instead of 157

例如输出:输入input = 10011101,然后二进制值为3534200而不是157

After surfing the internet for the formula in converting binary value to decimal, this is the reference I took for making this program.

在浏览互联网以获取将二进制值转换为十进制的公式后,这是我为制作此程序所采用的参考。

1*2^7 + 0*2^6 + 0*2^5 + 1*2^4 + 1*2^3 + 1*2^2 + 0*2^1 + 1*2^0 = 157.

1 * 2 ^ 7 + 0 * 2 ^ 6 + 0 * 2 ^ 5 + 1 * 2 ^ 4 + 1 * 2 ^ 3 + 1 * 2 ^ 2 + 0 * 2 ^ 1 + 1 * 2 ^ 0 = 157。

I tried the long version in making this program, in using for loop... I guess that's a dumb challenge? haha!

我在制作这个程序时尝试使用长版本,使用for循环...我猜这是一个愚蠢的挑战?哈哈!

here's the code(w/ comments!):

这是代码(带评论!):

byte binary[] = new byte[127];   //declared a byte array for input value
int power = 2, formula = 0;      //declared the power and the formula as int
System.out.print("Enter Binary: "); //prints "Enter binary:"
System.in.read(binary);          //inserts the input in the binary array
Integer bin = Integer.parseInt(new String(binary).trim()); //converts the input value to int for another conversion
String b = Integer.toString(bin); //converts the int bin to string
Integer num = Integer.parseInt(new String(b.substring(b.length() - 1).trim())); 
//num variable gets the value of last string (should be anyway)
System.out.println("The Decimal Value of " + bin + " is ");
for(int i = b.length(); i > 0; i--){ 
    for(int a = i; a > 0; a--){ //the condition
        power = power*2;        //as the loop goes, if 2^3 then it should be 8
    }
    formula = formula + (num * (power)); //as the given formula above, this is what I did
    System.out.println("power: " + power);//if you want reference, I left it here
    System.out.println("formula: " +formula);
    System.out.println("num: " + num);

    num = Integer.parseInt(new String(b.substring(i - 1).trim())); //uhm dunno how to describe this, but you'll see
    power = 2;
}
System.out.print(formula);

} }

ever since I started using java, this is the only thing that I know. (refer to my last question since sep 4)

自从我开始使用java以来,这是我所知道的唯一事情。 (参考我自4月4日以来的最后一个问题)

please help :(

请帮忙 :(

1 个解决方案

#1

You have a number of problems:

你有很多问题:

1) Integer.parseInt(new String(binary).trim()) does not do what you think it does. Therefore, your num is wrong.

1)Integer.parseInt(new String(binary).trim())不会按照您的想法执行。因此,你的数字是错误的。

2) You calculate your power wrong.

2)你计算错误的力量。

3) A general advice, put some empty lines to separate your code into small blocks that make sense. It will be easier on the eyes.

3)一般性的建议,用一些空行将代码分成有意义的小块。它会更容易在眼睛上。

The fixed program should look like this:

固定程序应如下所示:

public static void main(String[] args) throws IOException {
    byte binary[] = new byte[127];   //declared a byte array for input value
    int power = 2, formula = 0;      //declared the power and the formula as int

    System.out.print("Enter Binary: "); //prints "Enter binary:"
    System.in.read(binary);          //inserts the input in the binary array
    Integer bin = Integer.parseInt(new String(binary).trim()); //converts the input value to int for another conversion

    String b = Integer.toString(bin); //converts the int bin to string
    Integer num; //num variable gets the value of last string (should be anyway)
    System.out.println("The Decimal Value of " + bin + " is ");

    for(int i = b.length(); i > 0; i--){ 
        power = 1;
        num = Integer.parseInt(Character.toString(b.charAt(i-1)));

        for(int a = i; a < b.length(); a++){ //the condition
            power = power*2;        //as the loop goes, if 2^3 then it should be 8
        }

        formula = formula + (num * (power)); //as the given formula above, this is what I did
        System.out.println("power: " + power);//if you want reference, I left it here
        System.out.println("formula: " +formula);
        System.out.println("num: " + num);
    }
    System.out.print(formula);
}

#1