44 lines
1.3 KiB
Markdown
44 lines
1.3 KiB
Markdown
# Binary
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Write a program that will convert a binary number, represented as a string (e.g. '101010'), to its decimal equivalent using first principles
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Implement binary to decimal conversion. Given a binary input
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string, your program should produce a decimal output. The
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program should handle invalid inputs.
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## Note
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- Implement the conversion yourself.
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Do not use something else to perform the conversion for you.
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## About Binary (Base-2)
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Decimal is a base-10 system.
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A number 23 in base 10 notation can be understood
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as a linear combination of powers of 10:
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- The rightmost digit gets multiplied by 10^0 = 1
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- The next number gets multiplied by 10^1 = 10
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- ...
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- The *n*th number gets multiplied by 10^*(n-1)*.
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- All these values are summed.
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So: `23 => 2*10^1 + 3*10^0 => 2*10 + 3*1 = 23 base 10`
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Binary is similar, but uses powers of 2 rather than powers of 10.
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So: `101 => 1*2^2 + 0*2^1 + 1*2^0 => 1*4 + 0*2 + 1*1 => 4 + 1 => 5 base 10`.
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To run the tests simply run the command `go test` in the exercise directory.
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If the test suite contains benchmarks, you can run these with the `-bench`
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flag:
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go test -bench .
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For more detailed info about the Go track see the [help
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page](http://exercism.io/languages/go).
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## Source
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All of Computer Science [view source](http://www.wolframalpha.com/input/?i=binary&a=*C.binary-_*MathWorld-)
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