RaspberryBASIC.org Forum

[John]

Thanks!

I forgot to do Ruby for round three. There is a round two Ruby post in the challenge.

[jalih]

Anyway, I'm looking forward to seeing how you choose to implement this, Jalih.

I will post my fully featured version for 8th using simple string builder later when I get back home. Here is naive version using dynamic buffers. Size of buffers is initially 0.

Code: [Select]

1000000 constant LIMIT

a:new 0 a:push var, a
0 b:new true b:writable var, s
0 b:new true b:writable var, t


: iterate
  s @ "" 2 pick n:1- 26 n:mod 65 n:+ s:+ b:append
  b:len 26 n:< not if
    t @ swap b:append drop
    0 b:new true b:writable s !
  else
    drop
  then
  a:push ;

: app:main
  a @ ' iterate 1 LIMIT loop
  t @ b:rev >s s:len "r LEN: %d\n" s:strfmt .
  dup 26 s:lsub "Front: %s\n" s:strfmt .
  26 s:rsub "Back:  %s\n" s:strfmt .
  LIMIT a:@ nip "UBVal: %d\n" s:strfmt .
  bye ;

RPI binary

[John]

AIR,

I seem to have a problem compiling your latest C  code.


pi@RPi4B:~/c-dev/examples $ gcc -O3 1mil3-3.c  $(pkg-config --libs --cflags glib-2.0) -o 1mil3-3
1mil3-3.c: In function ‘main’:
1mil3-3.c:28:9: error: expected declaration or statement at end of input
         g_string_free (t,TRUE);
         ^~~~~~~~~~~~~
pi@RPi4B:~/c-dev/examples $

[AIR]

Usually caused by a missing bracket or semi-colon.  You sure you copied all of the code including end bracket?

Edit:  I copy/pasted from the post onto another machine (a mac), compiled/executed fine here.

[John]

Yep. Missed the final }.

Suggestion: Put your code tags on separate lines. I have got caught before not copying your code tags which had code attached.

[AIR]

Rust.  Not liking this one too much personally from a syntax standpoint, but you had asked for a Rust submission in the beginning...

Code: Text

1. fn main() {
2.     let mut s = "".to_string();
3.     let mut t = "".to_string();
4.     let mut a = [0;1000001];
5.  
6.     for x in 0..1000001 {
7.         a[x] = x;
8.         let b   = ( x%26 ) as u8;
9.         let c = ( b+65 ) as char;
10.         s.push( c );
11.         if s.len() == 26 {
12.             let reversed: String = s.chars().rev().collect();
13.             t.push_str( &reversed );
14.             s.clear();
15.         }
16.     }
17.     println!( "r LEN: {}",  t.len() );
18.     println!( "Front: {}",  &t[..26] );
19.     println!( "Back:  {}",  &t[t.len()-26..]);
20.     println!( "UBVal: {}",  a[1000000] );
21.  
22. }
23.  

riveraa@rpi:~/Projects/rust/1mil3/mil $ timex target/release/mil
r LEN: 999986
Front: ZYXWVUTSRQPONMLKJIHGFEDCBA
Back:  ZYXWVUTSRQPONMLKJIHGFEDCBA
UBVal: 1000000
0.07user 0.02system 0:00.10elapsed 99%CPU (0avgtext+0avgdata 6356maxresident)k
0inputs+0outputs (0major+1392minor)pagefaults 0swaps

AIR.

EDIT: arm binary attached.

[John]

Thanks Air for the rust submission. Can you attach the binary so I don't have to install Rust?

Damn. That is one big executable. If Microsoft rewrites Windows in Rust, you will need a terabyte of space just to load the OS.

rwxr-xr-x 1 pi pi 2582500 Dec  9 17:47 1mil3

pi@RPi4B:~/rust-dev/examples $ timex ./1mil3
r LEN: 999986
Front: ZYXWVUTSRQPONMLKJIHGFEDCBA
Back:  ZYXWVUTSRQPONMLKJIHGFEDCBA
UBVal: 1000000
0.10user 0.02system 0:00.12elapsed 96%CPU (0avgtext+0avgdata 6336maxresident)k
0inputs+0outputs (0major+1392minor)pagefaults 0swaps
pi@RPi4B:~/rust-dev/examples $

[John]

The ARM Swift maintainer posted an alternative to my script which I'll try and post its results.

No improvement with his substitute string reverse function.

Code: Text

1. // Swift 5.1.2 - 1mil3-2.swift
2.  
3. var s = ""
4. var t = ""
5. var a = [Int]()
6.  
7. for x in 1...1000000 {
8.   s += String(UnicodeScalar(UInt8(((x - 1) % 26) + 65)))
9.   a.append(x)
10.   if s.count == 26 {
11.     t += s
12.     s = ""
13.   }
14. }
15.  
16. var r = Array(t)
17. let count = t.count
18. for i in 0..<count/2 {
19.   r.swapAt(i, count - ((i + 1) as Int))
20. }
21.  
22. let revstr=String(r)
23.  
24. print("r LEN: ", revstr.count)
25. print("Front: \(revstr.prefix(26))")
26. print("Back:  \(revstr.suffix(26))")
27. print("UBVal: ", a[100000 - 1])
28.  

pi@RPi4B:~/swift-dev/examples $ timex ./main
r LEN:  999986
Front: ZYXWVUTSRQPONMLKJIHGFEDCBA
Back:  ZYXWVUTSRQPONMLKJIHGFEDCBA
UBVal:  100000
317.29user 0.09system 5:17.71elapsed 99%CPU (0avgtext+0avgdata 25444maxresident)k
7096inputs+0outputs (32major+6377minor)pagefaults 0swaps
pi@RPi4B:~/swift-dev/examples $

[AIR]

Old School (Pascal)
FreePascal:

Code: Pascal

1. program mil;
2.  
3. Uses StrUtils;
4.  
5. var
6.     s:AnsiString;
7.     t:AnsiString;
8.     c:AnsiChar;
9.     a:array[0..1000001] of int32;
10.     x:int32;
11. begin
12.     s := '';
13.     t := '';
14.     for x := 0 to 1000001 do
15.     begin
16.         c :=  chr( (x mod 26)+65 );
17.         a[x] := x;
18.         s += c;
19.         if Length(s) = 26 then
20.         begin
21.             t += ReverseString(s);
22.             s := '';
23.         end;
24.     end;
25.  
26.     writeln( 'r len: ', Length(t) );
27.     writeln( 'Front: ', LeftStr(t,26) );
28.     writeln( 'Back:  ', RightStr(t,26) );
29.     writeln( 'UBVal: ', a[1000000]);
30. end.
31.  
32.  

riveraa@rpi:~/Projects/fpc/1mil3 $ fpc -O3 -XX -Xs  mil.pas

riveraa@rpi:~/Projects/fpc/1mil3 $ timex ./mil
r len: 999986
Front: ZYXWVUTSRQPONMLKJIHGFEDCBA
Back:  ZYXWVUTSRQPONMLKJIHGFEDCBA
UBVal: 1000000
0.19user 0.02system 0:00.22elapsed 99%CPU (0avgtext+0avgdata 5604maxresident)k
0inputs+0outputs (0major+1430minor)pagefaults 0swaps

AIR.

EDIT:  Binary attached.

[John]

Wow!

You're like a language machine.   

[AIR]

Pascal was my first "REAL" language (via Delphi 6 on Windows a long time ago).

As far a Swift:  The problem is not the Reverse, the problem is the adding to the string.  Looks like it's creating a new string each time you try to add to it.

Try changing "+=" to ".append". like this:

Code: Text

1. s.append(String(UnicodeScalar(UInt8(((x - 1) % 26) + 65))))

and

Code: Text

1. t.append(s)

On my Mac, with the array portion commented out, it took the execution from 0m2.056s down to 0m0.673s.

The next biggest issue is all of the intermediate objects that are created with the crazy casting you have to do to get the integer over to a Character then to a String.  That adds up quickly with the loop we have going.

AIR.

[AIR]

John, try this:

Code: Text

1. / Swift 5.1.2 - 1mil3.swift
2.  
3. var s = ""
4. var t = ""
5. var a = [Int](repeating: 0, count: 1000001)
6.  
7. for x in 1...1000000 {
8.   let c = (x - 1) % 26
9.   s.append(String(UnicodeScalar(UInt8(c + 65))))
10.   a[x] = x
11.   if c == 25 {
12.     t.append(String(s.reversed()))
13.     s = ""
14.   }
15. }
16.  
17. // let r = t
18.  
19. print("r LEN: ", t.count)
20. print("Front: \(t.prefix(26))")
21. print("Back:  \(t.suffix(26))")
22. print("UBVal: ", a[100000])
23.  
24.  

On my Mac, not installing Swift on my RPI:


[riveraa@mini ~/Projects/Swift/1mil3] $ swift build -c release
Compile Swift Module '_mil3' (1 sources)
Linking ./.build/x86_64-apple-macosx10.10/release/1mil3
[riveraa@mini ~/Projects/Swift/1mil3] $ time .build/release/1mil3
r LEN:  999986
Front: ZYXWVUTSRQPONMLKJIHGFEDCBA
Back:  ZYXWVUTSRQPONMLKJIHGFEDCBA
UBVal:  100000

real    0m0.338s
user    0m0.323s
sys    0m0.010s

AIR.

[John]

With the append and doing string reverse on  the fly, we went from 5 minutes to 43 seconds.

Code: Text

1. // Swift 5.1.2 - 1mil3-2.swift
2.  
3. var s = ""
4. var t = ""
5. var a = [Int]()
6.  
7. for x in 1...1000000 {
8.   s.append(String(UnicodeScalar(UInt8(((x - 1) % 26) + 65))))
9.   a.append(x)
10.   if s.count == 26 {
11.     let r = String(s.reversed())
12.     t.append(r)
13.     s = ""
14.   }
15. }
16.  
17. print("t LEN: ", t.count)
18. print("Front: \(t.prefix(26))")
19. print("Back:  \(t.suffix(26))")
20. print("UBVal: ", a[100000 - 1])
21.  

pi@RPi4B:~/swift-dev/examples $ swiftc  1mil3-2.swift
pi@RPi4B:~/swift-dev/examples $ timex ./main
t LEN:  999986
Front: ZYXWVUTSRQPONMLKJIHGFEDCBA
Back:  ZYXWVUTSRQPONMLKJIHGFEDCBA
UBVal:  100000
43.64user 0.03system 0:43.69elapsed 99%CPU (0avgtext+0avgdata 12984maxresident)k
0inputs+0outputs (0major+2929minor)pagefaults 0swaps
pi@RPi4B:~/swift-dev/examples $

[AIR]

Try what I posted, making sure you build in "release" mode.  Default is "debug", which is slower.

[riveraa@mini ~/Projects/Swift/1mil3] $ /usr/bin/time .build/release/1mil3
r LEN:  999986
Front: ZYXWVUTSRQPONMLKJIHGFEDCBA
Back:  ZYXWVUTSRQPONMLKJIHGFEDCBA
UBVal:  100000
        0.32 real         0.31 user         0.00 sys

/usr/bin/time is different on Mac.

AIR.

[John]

I use swiftc to compile.

Your latest cut it in  half again.

Code: Text

1. // Swift 5.1.2 - 1mil3-3.swift
2.  
3. var s = ""
4. var t = ""
5. var a = [Int](repeating: 0, count: 1000001)
6.  
7. for x in 1...1000000 {
8.   let c = (x - 1) % 26
9.   s.append(String(UnicodeScalar(UInt8(c + 65))))
10.   a[x] = x
11.   if c == 25 {
12.     t.append(String(s.reversed()))
13.     s = ""
14.   }
15. }
16.  
17. print("t LEN: ", t.count)
18. print("Front: \(t.prefix(26))")
19. print("Back:  \(t.suffix(26))")
20. print("UBVal: ", a[100000])
21.  

pi@RPi4B:~/swift-dev/examples $ swiftc  1mil3-3.swift
pi@RPi4B:~/swift-dev/examples $ timex ./main
t LEN:  999986
Front: ZYXWVUTSRQPONMLKJIHGFEDCBA
Back:  ZYXWVUTSRQPONMLKJIHGFEDCBA
UBVal:  100000
24.09user 0.04system 0:24.19elapsed 99%CPU (0avgtext+0avgdata 12656maxresident)k
0inputs+0outputs (0major+1907minor)pagefaults 0swaps
pi@RPi4B:~/swift-dev/examples $