Contents

# Binary

Convert a binary number, represented as a string (e.g. '101010'), to its decimal equivalent using first principles.

Implement binary to decimal conversion. Given a binary input
string, your program should produce a decimal output. The
program should handle invalid inputs.

## Note

- Implement the conversion yourself.
  Do not use something else to perform the conversion for you.

## About Binary (Base-2)

Decimal is a base-10 system.

A number 23 in base 10 notation can be understood
as a linear combination of powers of 10:

- The rightmost digit gets multiplied by 10^0 = 1
- The next number gets multiplied by 10^1 = 10
- ...
- The *n*th number gets multiplied by 10^*(n-1)*.
- All these values are summed.

So: `23 => 2*10^1 + 3*10^0 => 2*10 + 3*1 = 23 base 10`

Binary is similar, but uses powers of 2 rather than powers of 10.

So: `101 => 1*2^2 + 0*2^1 + 1*2^0 => 1*4 + 0*2 + 1*1 => 4 + 1 => 5 base 10`.



## Source

All of Computer Science [http://www.wolframalpha.com/input/?i=binary&a=*C.binary-_*MathWorld-](http://www.wolframalpha.com/input/?i=binary&a=*C.binary-_*MathWorld-)

## Submitting Incomplete Solutions
It's possible to submit an incomplete solution so you can see how others have completed the exercise.

Version data entries

133 entries across 133 versions & 1 rubygems

Version	Path
trackler-2.2.1.159	tracks/kotlin/exercises/binary/README.md
trackler-2.2.1.158	tracks/kotlin/exercises/binary/README.md
trackler-2.2.1.157	tracks/kotlin/exercises/binary/README.md
trackler-2.2.1.156	tracks/kotlin/exercises/binary/README.md
trackler-2.2.1.155	tracks/kotlin/exercises/binary/README.md
trackler-2.2.1.154	tracks/kotlin/exercises/binary/README.md
trackler-2.2.1.153	tracks/kotlin/exercises/binary/README.md
trackler-2.2.1.152	tracks/kotlin/exercises/binary/README.md
trackler-2.2.1.151	tracks/kotlin/exercises/binary/README.md
trackler-2.2.1.150	tracks/kotlin/exercises/binary/README.md
trackler-2.2.1.149	tracks/kotlin/exercises/binary/README.md
trackler-2.2.1.148	tracks/kotlin/exercises/binary/README.md
trackler-2.2.1.147	tracks/kotlin/exercises/binary/README.md
trackler-2.2.1.146	tracks/kotlin/exercises/binary/README.md
trackler-2.2.1.145	tracks/kotlin/exercises/binary/README.md
trackler-2.2.1.144	tracks/kotlin/exercises/binary/README.md
trackler-2.2.1.143	tracks/kotlin/exercises/binary/README.md
trackler-2.2.1.142	tracks/kotlin/exercises/binary/README.md
trackler-2.2.1.141	tracks/kotlin/exercises/binary/README.md
trackler-2.2.1.140	tracks/kotlin/exercises/binary/README.md