Hi Guys,

I was involved in a coding challenge to calculate 2 pi r,

the circumference of a circle, given the radius as input, without any multiplication, division, or floats,

so I pretended I was using an 8 bit pic It was done in C, but all variables were integers,

so hopefully this BASIC is a good representation. (only the C was tested).

Cheers

Code:

var word input = 300 ‘ input radius
var byte twopi[19] = { 0x00,0x00,0x00,0x06,0x02,0x08,0x03,0x01,0x08,0x05,0x03,0x00,0x07,0x01,0x07,0x09,0x05,0x09,0x00 }
var byte otput[19] = { 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 }
var word adcnt = 0 ‘ counter
var byte dgcnt = 0 ‘ digit index
var byte carry = 0 ‘ carry digit
while (adcnt < input) ‘ multiply through addition
dgcnt = 17 : carry = 0
while (dgcnt > 0) ‘ cycle the digits
otput[dgcnt] = otput[dgcnt] + twopi[dgcnt] + carry : carry = 0 ‘ add digit
if (otput[dgcnt] > 9)
otput[dgcnt] = otput[dgcnt] - 10 : carry = 1
endif ‘ carry digit
dgcnt = dgcnt - 1
wend ‘ dgcnt
if (carry != 0)
otput[dgcnt] = otput[dgcnt] + 1
endif
adcnt = adcnt + 1
wend ‘ adcnt
twopi[18] = 0 // terminate string
// answer: 1884.9555921538758 is the string in the otput array

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