Converting int to string in java is giving the answer as 1

Question

I converted a decimal integer to binary and that binary integer when I'm trying to convert to a string is giving me 1 as the answer always when it should give the value of the string.

         while(a>0) 
         {
             b = a%2;
             n = b;
             a = a/2;
         System.out.print(n);
         }

        String m = Integer.toString(n);
         System.out.print(m);

Any corrections and suggestions would be much appreciated.

Thanks!

I don't understand what you were expecting to see, the word 'one' ?? — smoggers, Dec 18 '15 at 15:54
```String m = Integer.toString(a, 2); System.out.print(m);``` — , Dec 18 '15 at 16:09
@smoggers I'm trying to say, for eg if I take a=13, I'm getting n=1011 as the output (which is in reverse but thats the issue right now). So, when I'm converting this integer value n to string, instead of showing "1011" its giving me 1 as the output. — Megha, Dec 18 '15 at 16:13

Konstantin Yovkov · Accepted Answer · 2015-12-18T15:58:37.253

4

On every loop step, you have these two statements:

b = a % 2;
n = b;

Think about why all the possible values of n are 0 and 1?

It's because n copies the value of b, which is the value of a modulo 2, which is always 0 or 1.

The last value of n will be the left-most bit of the binary representation of a, which will be always 1 (unless a is 0) and this is why you always get 1 when printing m.

edited Dec 18 '15 at 15:58

answered Dec 18 '15 at 15:55

Konstantin Yovkov

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So basically just the last value of n is getting stored? Alright, got the problem, thanks! – Megha Dec 18 '15 at 16:14

score 2 · Answer 2 · answered Dec 18 '15 at 15:57

When you use

n = b;

you are replacing the value of n each time. What you want it to accumulate the bits in n. The simplest way to do this is to use a StringBuilder.

StringBuilder sb = new StringBuilder();
while (a > 0) {
    int lowest = a & 1;
    sb.insert(0, lowest);
    a = a >>> 1; // shift the bits down by 1.
}

String m = sb.toString();
System.out.print(m);

This will do the same thing as Integer.toString(a, 2)

Converting int to string in java is giving the answer as 1

2 Answers2