Author Topic: Number inversion (Read 6973 times)

someone · « **Reply #15 on:** November 15, 2012, 11:52:04 am »

If the goto is to repeat the process or end it, you could call the function again inside the code (recursion) or end it using a return.

Eeems · « **Reply #16 on:** November 15, 2012, 12:02:39 pm »

Code: [Select]

Local final,reps,next,a
f=103
while f!=998
	num=f
	final=0
	reps=int(log(num,10))+1
	For a,0,reps
		next=int(((num)/(10)))
		final=final*10+num-10*next
		num=next
	EndFor
	resulti=((final)/(10))
	num=resulti-f
	l=num
	Disp "O Inverso de ",f," é ",resulti," logo"
	Disp resulti,"-",f,"=",l
	Local final,reps,next,a
	final=0
	reps=int(log(num,10))+1
	For a,0,reps
		next=int(((num)/(10)))
		final=final*10+num-10*next
		num=next
	EndFor
	resultii=((final)/(10))
	Disp "O inverso de ",l," é ",resultii," logo"
	Disp resultii,"+",l,"=",resultii+l
	while !<reasons>
		f=f+1
	EndWhile
EndWhile

This would probably work. replace <reasons> with all the checks. Also, keep in mind this is psuedo code, it might need some altering to work.

someone · « **Reply #17 on:** November 15, 2012, 02:20:10 pm »

Quote from: joao9856 on November 15, 2012, 11:34:29 am

Is there any way of making this code run faster(i'm kinda newb here!)

The language is Portuguese and its says like this:
301 is the mirror for 103 then:
301-103=198
891 is the mirror for 198 then:
891+198=1089
and so on..

Something I don't understand is the criteria to stop the program. The first time you do a subtraction of abs(mirror(number)-number) and then you do the same but with an addition over and over? ( abs(mirror(number)+number) ). How many times should it go before stopping?

BTW, if you create a function rather than a program, you can use the output as the next input (either with another function/program or in the Calculator). You could even place it under MyLib & have your own function:

Code: [Select]

Define LibPub mirror(input)=
Func
©mirror(input) mirrors "input" -> "tupni"
Local flip,n,i
  input:=string(input)
  n:=dim(input)
  flip:=mid(input,n,1)
  For i,1,n-1
    flip:=flip&mid(input,n-i,1)
  EndFor
  Return expr(flip)
EndFunc

If is only a subtraction, then sooner or later should stop in 0 (when the number is a palindrome). Something you can do using the calculator (with the code posted) could be:
* Type first the number you want to use as "ans", e.g. "103"
* Type "abs(mirror(ans)-ans)"
* hit enter several times until you reach 0

joao9856 · « **Reply #18 on:** November 15, 2012, 03:20:39 pm »

The idea is in the spoiler, i think that is all i wanna do( need to check mannually

all of it)
Its a pretty huge print for a calc to make but i always liked things big.
the idea is to see if every number mirror plus its mirror gives 1089.
rules are:
The smallest number must be 103
The number must not be equally read from the beginning to the and or from the the to the beginning(If they were it wouldn't make sense to mirror them)
The first number decides the biggest last number EX: if the first number is 4 the smallest last number can only be 6(allways up to 9)) or be it n+2 for the smallest.
And if i'm not mistaken thats it!
The SPOILER IS HUGE!

Spoiler For Spoiler:

someone · « **Reply #19 on:** November 15, 2012, 05:43:29 pm »

Quote from: joao9856 on November 15, 2012, 03:20:39 pm

The idea is in the spoiler, i think that is all i wanna do( need to check manually all of it)
Its a pretty huge print for a calc to make but i always liked things big.
the idea is to see if every number mirror plus its mirror gives 1089.

rules are:
The smallest number must be 103
The number must not be equally read from the beginning to the and or from the the to the beginning(If they were it wouldn't make sense to mirror them)
The first number decides the biggest last number EX: if the first number is 4 the smallest last number can only be 6(allways up to 9)) or be it n+2 for the smallest.
And if i'm not mistaken thats it!

Well, not every number satisfy the condition, e.g. 998 is not a palindrome (a number that is the same if read left to right or right to left).

If you use the code I posted earlier (which I called "mirror()"), you can print something like in the spoiler with the following function:

Code: [Select]

Define main()=
Func
  Local i,r1,r2,minus,plus
  For i,100,999
    r1:=mirror(i)
    minus:=abs(r1-i)
    r2:=mirror(minus)
    plus:=r2+minus
    If plus=1089 Then
      Disp "O Inverso de",i," é ",r1,"logo:"
      Disp max(r1,i),"-",min(r1,i),"=",minus
      Disp "O inverso de ",minus," é ",r2,"logo:"
      Disp r2,"+",minus,"=",plus
      Disp ""
    EndIf
  EndFor
EndFunc

joao9856 · « **Reply #20 on:** November 15, 2012, 06:11:51 pm »

I guess something like that should work, its just that i never worked with functions before...

someone · « **Reply #21 on:** November 15, 2012, 07:11:36 pm »

Looking at the output, it seems that the answer to that problem is that all 3 digit numbers (starting from 100, since for example 012 is not valid as is actually a 2 digit number) minus the ternaries composed of: palindrome-1, palindrome, palindrome+1, will give an output of 1089.

So, the first palindrome is 101. That means that 100, 101 & 102 are excluded, then the second palindrome which is 111 means that 110, 111 & 112 are out, and so on until you get to 999 which excludes 998 & 999, since 1000 is a 4 digit number...

In summary there are 3 cases:
* If number is palindrome, answer = 0
* If number is palindrome +/- 1, answer = 198
* else, answer = 1089

ElementCoder · « **Reply #22 on:** November 16, 2012, 02:23:02 am »

Quote from: joao9856 on November 15, 2012, 06:11:51 pm

I guess something like that should work, its just that i never worked with functions before...

It's really simple

A program just runs and then terminates. You can't do anything with it so to say. Functions however return a value. So say you have the following situation:

Code: [Select]

Define main()=
Prgm
    a=3
    b=4
    c=a+b
EndPrgm

Code: [Select]

Define main()=
Func
    a=3
    b=4
    c=a+b
EndFunc

The program just does a+b and then stops. The function does a+b and returns the answer (7).

Not sure anymore if functions need a return or not?

Author Topic: Number inversion (Read 6973 times)

someone

Re: Number inversion

Eeems

Re: Number inversion

someone

Re: Number inversion

joao9856

Re: Number inversion

someone

Re: Number inversion

joao9856

Re: Number inversion

someone

Re: Number inversion

ElementCoder

Re: Number inversion