Prefix Notation

I could do with some prefix notation practice (I have not reached Satori).

To this end, I'd be terribly obliged if you could post some nested mathematical expressions with nested brackets and only simple (+ - * /) operators, so I can practice converting them.

I'd also be obliged if you could tell me if I'm right/advise me where I'm going wrong.

An example;
7(8 x 9(10 x 3(8 + 4)))
(* 7 (* 8 (* 9 (* 10 (* 3 (+ 8 4 ) ) ) ) ) )

Am I right? Wrong? Advice?

>>1
You're semantically right, but both your infix and prefix notation versions are ludicrous.
7 * 8 * 9 * 10 * 3 * (8 + 4) = (* 7 8 9 10 3 (+ 8 4))

(+ 4 1 ( * 3 7 ) (/ 2 4))

(/ (+ 3 3 5) (- (* 2 5) (+ 4 6)))

>>2
So, technically right, just need to clean it up? Thank you very much :D

A supportive IRC-er gave me a monster one to solve - namely
(6(9-8*2(4-5)+7-4(2*3)+4-8))/(5(3(7-3)(2+1)-8+9-4))

With my shitty, uncleaned-up code, I got
(* 6 (+ (- 9 (+ (* 8 2 (- 4 5 ) ) 7 (* (- 4 (* 2 3 ) ) ) 4 (- 8 ) ) ) ) (/ (* 5 (* 3 (+ (- 7 3 ) (+ 2 1 ) (- 8 ) 9 (- 4 ) ) ) ) ) )

Let me just clean it up and I should be able to figure out if I'm right - the REPL says the answer is 12/5

^{) ) ) ) ) )
) ) ) ) ) )}
 ) ) ) ) ) )
 ） ） ） ） ） ）
） ） ） ） ） ）
） ） ） ） ） ）

(+ 4 1 ( * 3 7 ) (/ 2 4))
4 + 1(3 x 7)(2 / 4)
4 + (3 x 7)(2 / 4)

Sorry if it isn't clean, but this is the easiest format for me to read.

Solution is; 4 + 21 x 1/2 = 14.5(?)

(/ (+ 3 3 5) (- (* 2 5) (+ 4 6)))
(3 + 3 + 5)
           /
            (2 * 5) (4 + 6)

11 / 100 (Eleven hundredths)

>>6
Thanks, I'll need those.

Is this thread a joke?

>>7
That's all wrong.

>>10
Specific examples and corrections? :(

>>9
No.

>>11
(+ 4 1 (* 3 7) (/ 2 4)) = 4+1+3*7+2/4 = 5+21+1/2

(/ (+ 3 3 5) (- (* 2 5) (+ 4 6))) = 11 / (10 - 10) = OH SHI-

So, why are you doing this? How often will you be translating over-complex badly notated infix expressions to prefix notation? My guess is never.

>>13
When not using toy programming languages, they like to come up with toy logic/mathematic challenges.

>>14
So you think the problem that he's not spending enough time coding?

can I say something? the prefix notation is suprisingly cleaner

>>16
That's often the case. When you're summing (or whatever) a bunch of things, prefix notation wins hard (+ 1 2 3 ... n) is really compact. On the other hand, complex formulae often take way too much typing (* 440 (expt 2 (/ 7 12))) versus 440*2^(7/12). Trade-off either way.

ummmmm,
just use the super easy stack based infix<->prefix algorithm.

It's fukin cool as beans.

>>12
Lol'd @ the 2nd

Also, whoever set me the impossible divide by 0 one is a bastard.

>>5
(6(9-8*2(4-5)+7-4(2*3)+4-8))/(5(3(7-3)(2+1)-8+9-4))
turns to
(/
     (* 6
         (+ 9 (* 2 -8 (- 4 5)) 7 -4 (* 2 3) 4 -8))
     (* 5
         (+ (* 3 (- 7 3) (+ 2 1)) -8 9 -4)))

not so bad. Also, I'd insist it's cleaner.

(1-9+(7/1-(5+6*(2/(7/6+3)))-((5+6-4/4*((((1*6)-1*7-(3+((6*4)+(2/1/3)*7*8-1+(8*8+4))/4/5+1))/8/7)-9+(4*9*8)*8)/(5/4*((6/8/4)/(8+(6-1)/6+2*(4-6+((2*9)/(3-1/9+4/4)/(3+9/6-9)+7*5)-(1*(6*9*8/7+4)*6)-9))*9/(2-4)*7-(6-3/7-3*1)))-9)+4+(8/5+6+(3-9*(((7*8*3*4*(2*3+4+5+(7+4/8-8-5*6-7)-(6/4-8*4)))/2+7)+4+7/(9+4)-(1/(1/5*(6-7+5/5*4/8)/8/7)))+8-9/7)-(4+(1+4/(6-5)*4)/3-(((5*(7-(3+8/5)))/1-(2/3+2+3/((4+2+3)/7*(2*4)-3+(1/6-3)*3*(7+4*8/4*6+7))+(9+3-3-(2-5-1/1-1*5)-1*(1-3+4/2+5)))-1)-(2*((2+8-8*3-7)+2+6)-3-(((8+4-2-5-7)+(1-6-2*3))*(1+2)/((2/6*6)/3+2-8/(8*2/4-5)+(4-9*1*3))-3+1/(9/9/(3+3-8*2/3)/2))*(2/2*8-3+(2*2+(1*7/8/1+4*5)*5))+(5/5/4-5))-9-5-(1/(((5*9+4+3+8+5+9)/8+1-9+9+3)-((8/3+1-4*8+3)*2*9+6)+5+((5+4+6-6-9+9-7)+2*(8*5*5*7)*3+7+5))/2+9/(((4*7*8)*1)-3-7*(6/(1+9*2)+(1+8*5*4)*(2-4/3-8-7)/(4+7*8)-(1+5-6*9*3+7-9)))/1)+6*9)-(4-6+7+(8-((3-3+(1*1*3-8/7)/9)+8/((5*2*1-9/8*5)/6-5-2+(7+7/5*8*5*2+2)/(7*5/6-6)-(8*1+2/8)))*3+(4*6-6-(1-6/4-9-5))/6)+(((8+(3+9+8+7+9)-(5/1))-(8*1)-5)-(8/7)/(((8/7*3/3/7/1+9)/2+1/2*9)*6/6*(4-4-3-(1*3/8+6/4))/2*9))*4+2)*1*((2/5)*6/((7*8)/4)/1))+(4-((3+9+7/6)+(5+2*7+((6*8/4+(7*7-3*1/2/1/3)-(7*5/2+9*6+5+2))-8)/9*9-6)+6-8-1)+1-7-5*7))/9-8*6*(1*2/8+4*(9+(1*8+(4+7/9*(1*8+3*2/2-9)-3)+(8-7/6-6+(1/((1+9)-8/9-8*3-9)/((5/2)*(5/2)*6+(4/3)-4+6)-(6-1)+(3-4/7/2)-((6*2-4/6+9+3/5)/2)+7)/1)-1)*7/4-5*8)-(1/3*(6+((4/(2+6*3/1+(3+8-2/6*2*4+5)-3+4)-(2*5*6-9*1-5)/8)/4*9+(8/8*(9+(6*5)+9/(5+9-9*6/1/6*1)+(8*2+1-9+8)*6*2)-8*5+(1*(8/1-8*3-4+2/6)/(6*9/2*7-5-9*4)*9))-4-((9*5+1*(1*7+9/1)/3)+4/3-(9-5/(5-9)-(5-1)*9-(7-8-7-2)-8)/(5-(7-2/7))/4)*(9*(1+8*(2+9)*7/9)-((7*3+3/1/5-4/3)/3/1*7+7)/((2/4)+4/7*(3/8/9/4*5-3)-9+5*(6+5+2-5-6+4))*((2-3*2/9-2+9)-(9+4-5/5)*1)*4*8))+4+((((3*4)*6/6*5+5-6)/(5*(7*7+6+1*7*1)*7+2+(4+9+3-9))*(4+3*3+6+5+6)-(8*4*1+5-(5*1/9/7+5+7)/1)+((6+9/1-7*3+1*3)-4/(8/8/2-3*6*4)+6/5+8)*6-3)*(5-1+(1+2+5)/9)+(9-1+((6/5+6/1/3)+4-9+6+2/(4+8+1+9/5+8/5))))/8+((8/8/4+((1-6/8-1)/5/3))/3+8-8/9+1)+4)/9*(5/7)*5)))+(4-2-2-(4/7-7/2*(5*(((3-2)*8+2-9)+4-1*9*(2/6-8))/8*3)+2*(((7*6*(4*1*(4-6-(9/8+3*2-3*2+2))-7/(7/(3/8+4-3+1*8+4)-5))+(((3+6*5)*9+(3/5-3+1+7)+9/(7/3/9)-6)/9*(6+1-6)-((8+6+7/9*1*3)*2-(8-6-5-2+7)/6+(9*1/4+1/3))/1)/4+(1*(2/7/(2+8/6+4-8/6))/((2-1*9)/1-(2+5))/(1/(1-3*8)-8+(7+3)+1)-5))/(5-3+5+5)/(9*(5+9-(6-1-3)+8/4-7/6))*7-3+4+(7/5*6*8/4*((7*5+1+(7+9+9/5*8-5*2))+6+(7/8/8+(7+5/4+7)/5)+8)+(2-((4+6/5)-(6/7-9*5/2)*8)+2*4)))+3+6-(7*(2*9*2+7+((6+4-(2/5-7-1/1+5)/1/9-1)*7-8-(2-4*(7+3-1*6+6*8/2)+(5*1)+8/(8/4/9*3)-(5/3/1/1/9))/1-8))*(5/8+5*9)/4*5/5*2)/9*(8+2/6-((6-6/((9/3)+8-7+(2/4+8-8/2+5)-8-(9+1+7*4)))+(7+8/(3*2*6-(9+8*7)-8*(8+1/4-5)/1)+4))-1))))/5/9)/5+3*(2*3+(5+(1-9/3-3*8)+6/6)-(3/5/2-((((1/8+3/6+(((8*8/8/2-5/6)/(3/3*7*2*2/4)+4-9-5+3/6)*8*(6/9-2)))+6)*5)/2)*((5+4-8*(1/6/7/7-6+((1*4+9)+((6-6/3+8+6)*6-4+5+5+(6*(5*3+6-8+3-1/3)/7-(1-2+2*1-8-5)+9))-(2+6+(3+7+9)*8+(8-4-(8*9*6)/(2/1-2/2*3)/(7+9*9-6-6)-2)/5)+5+2/3*6))/2)/3*9/((3-7-9-(((5*6-8)+5/4-(2/(1-7+5)/(1*1+3*6/2*7-5)-5+(7+2+5)-9/1))*3)*5)+7-2*1)-(8-7*6-7/2/6))/4)*3*7))+8-(4/(7*2-((9-4)*(8+4*8/4)-1-(6-3-1))*4+4/6*(8*1+1-9+(1/1-3-6)))-(7+(9/(5-(5/((2*1)/6+1-4+5/6)/5+(1/8/5-8/2)-5*8)/8-(8+3)/7/(8*5-(4*((9-9-2/((5*4-4)*(2/9/7-3-6+9*9)+3)+((8-6-1)-7+6/1*(3+7+5*7*4+8+2)+7)+5)*3*(2*6-4-8/4-((7+9*2*2+5*2*3)*(4*2*1*6)/7+4-2-8/7))/(8*(1-8+2/6/9+8*4)-1+2-(4/(1-5)*8)+5*2)*(6/((7-9)/(9*7+8*8)*(9*9+2/6-5-9)*7/1+(3*5-4-6-2)*1)+(1/3-5*6)-6+7*(7/6-(2*6-9*4*2+2-1)*8/(6*8-2+1-8-8)))*(((7+1-5-9/3+9)/6-6+(2*3+1+5*5)/(2-9+8))/(2*(8*1)+(8/4-2*2-1-4)+(9-5*3*6*3/8/1)/5/6))))-((7-(4-((9*7+7*8/2/1-4)/2+5*(2+8/7*9-8)*3/8)/7*5/(3/(1*7-6/1/6))+5)+((9*3+3+3+9-(3/2+6*3/9))+9*(4+(2-3-3)-9*4+(4/9-7)+2-(9+4-6/3-5))-5-3)/4)/(1/9-3-2-1-2)*2)*5/6-6)))/6*5-1-9/8)-(7*8*(3*8-4/6+7*4-((((2-7+(9+2)/((5*1*(4/7-3+8+8)+(6+7*5-7)*7/2-2)/(6-6-(9+2)/(3-5*7-2-8))/((3+6+8*3)-(7+5*1-5-6)-4/5/(7-3*9*2+5)/1-(2/2))+(2*(6+3-1*4)*4-1-7-1)*(7+(1*2-6)-5*(7-3*4*7))/(5/3-(1+4)+(7/7*4-8/3*6)/1))*(9+2*3+(5+2)+5)*5-8)+9/4+9*(7*1*9*((6/(5*1*6)-5-2)-(7+3*2)/5-((2-4)*9/5+(7/2/9-3*2)-9/(8+9*5-5*7)-(4*4))-7-(6+5-1+(6/9+7*6+4+7/2))+(6+7))*(7-7+3/8/4+3)*4))*2/(3+((4-((3/6-7+2)-3+3*7))+9+7-1-1)/7*3))/6*3+8+(6*(8-8))*6*4))+(9-7)*5+4)*7+8)-(4+(6/6*5/9-5-(3*(((1+(4/7-((6/5-(6*7+8*3+1*6/2)*9*(5-9/4*2*7/1*7)+3+(9-7-9-3-4*1))/((5/5*8/8*3+9/4)/(7-6-7/1+1/9/9)-(7+3+3*3*4+7)*4+5)/9*8/(6/(8/8+6+2+9*5)))-(4*((2*5)-8*(1*9-1*3)-3/5-7)+8+((8/3*5/3)+2-3*3)*7/((2/5)-2-(1/7+1-7)*(3-6)+5*(2+5/5)*7)*1)*8+6-6)+8-3+2/1)+2+2/(1/(2+(3+1-2+((5+3+5+3*2*7+6)-4*3+(3+2/5+1)*4)*(2-3/(1-5-3*4/4+8-2)))/(4*5)+(8-3-4*5*9-(3-(6/2+3/9*3)+5)/(5+1*(6*3)-1*(3/6/6-6-8)))+(3*((3-8+3)+6/(9+4-2*8+5)+6-(3+3+3+1))*(5*2*9-1/(5/5/1*4)/(8-6)*7)/9)*1)+(2*2)+((((1+1-1)/5*(1*3+1-1/3-9)/5*(3/1*6-1*4+7/9))*1/8+7)+((4-4+5)+3*5-((3*6+6*5/6+3+7)+(1*3/2/6)+(9/1-2/9-8*9)-6-7-8*(9+6*7)))/5+4-(4/2+7-((9+9-4-5-5/2*3)/1*4-1+2)+8)*5*2)+(6/7)-3)/5)-(2*3*8+((1+5-2+3*3*((6-7-(7/6+9*6)+(2-3-2+3)*6/9*(2/4/4))/8/9+((5+3*8)-1*7*1/(3*1-8)+4-2)-((7+8)-(2/4-1*7/1*5))))-((8+7)/(5-(3-(3+8/4/9))+8-(5-3+1)*6)*5*4/2*4-2))-(((3+6-4/(1+2+(8/7*6-2-2)-9-8-6/9)/8-9/1)*(6+((6-9)-5*2-1+(8/8+6*7*2*8)/3)+((3-5*5/9/4/8+4)+9*(6*6)-7+7+5+9)/3*4*6)/2+4)-(((8+7/9+5+2-6)/((1/2)*(1*1+9-2-1*2+1)/5+(8-7-3/3*7/8*2)+5)*6/3-3+(2-(5+8+9*5/7)/(4/7)/4-3/(4/8*2)))*(6-((9-9-6/7/6-2)*2*3)-6)*5/(5/7+6*(1/2-(8*6-2/5)/(2/1/6+1*2/2)*3)/4))-5-(5*1*(((8+6/4)*7/8+4)*8+((6*7+2+9+4/1)-(4-6/5+1-6-9))*7-9-(6/3-3)*3)*8-(3-9/4+2)*6/4)/(2/4-2*(1-9+(4+6+(9*1+5+8)+3*8)-7)/9)*4)-7-(((((2-6+8-4*8*2*3)/(9-4*6-6/4*6-8)-(2+4+8-2+9+2+8)/7-2/(7-4))/3+2*(4+(5-6)+9+6))*6-3)*3+6))*8)-8-(2-4-9/(7+8*(9-8+(9+3+2-9*(1+8*5*4/9)/9*4)+7/((7-7)-((5/8)-2-2/(2-4-3+8-3/9))-(9*9/(8/(6/4-2/6))+7/((3*5+2)+8+(5+7)*(9-3-4-4+3+7*6))))))-6/5/4)/1*7+9)-(6-(3*6)/2*7))*1-1/(9/4+9-7/3/3))

>>21
I came

>>21
Hot.

>>20
pretty-printing is fucking shit.

I'M THE SUSSMAN
SON OF A BITCH ABELSON
ABELSON IS PIG
DO YOU WANT PYTHON?
DO YOU WANT FORCED INDENTATION OF THE CODE?
ABELSON IS PIG DISGUSTING
GUIDO VAN ROSSUM IS A MURDERER
FUCKING ABELSON

I'M THE SUSSMAN
SON OF A BITCH ABELSON
ABELSON IS PIG
DO YOU WANT PYTHON?
DO YOU WANT FORCED INDENTATION OF THE CODE?
ABELSON IS PIG DISGUSTING
GUIDO VAN ROSSUM IS A MURDERER
FUCKING ABELSON

I'M THE SUSSMAN
SON OF A BITCH ABELSON
ABELSON IS PIG
DO YOU WANT PYTHON?
DO YOU WANT FORCED INDENTATION OF THE CODE?
ABELSON IS PIG DISGUSTING
GUIDO VAN ROSSUM IS A MURDERER
FUCKING ABELSON