Hello everybody!!

That's my little OS shell, called SimpleCS (yeah, it has a name!!!! )

Features:

1) Very small: less than 7000 bytes (actually it's about 6600 bytes)
2) Can setup the calculator more easily (Degree/Radian, Fix/Float, Sci). It can also change the name or the password, erase all the variables, but I'm still working on it because when I run my Tamagotchi and then my shell, everything from my Tamagotchi is erased  :'( /!\It is in another program, so that both are independant. Sadly, I didn't save it, and someone stole my calc   :'(
3) Can calculate Pythagore's Theory (sorry, I'm French, I don't know how it's named in english ), GCD, LCM, Statistics, areas (circle and this)
4) Can calculate special numbers for economy (in France, for francophones: élasticité, variation relative et taux de variation)
5) A program called TI-MSN, and BlackJack, Snake and Tic-Tac-Toe (these games are not running on the GRAPH screen, I'm very bad at GRAPH screen programming  )
6) Protected by password of anytype, can contain number as well as letter. /!\  This feature is in another program (the simplest in the world, just 1 line)
7) Displays your name at startup   (the most useful feature.....)

The problem is that it's in French, so the attached file is the french version. I also have the source code in a .txt document (available, just PM me and I will send it to you )
If you encounter any problem, tell me

For the password:

Input "PASSWORD?",Str9

For the username:

Input "USERNAME?",Str4

It's TI Basic, but full of errors:

Degree
ClrHome:ClrDraw:ClrTable
Disp "BONJOUR",STR4
Pause
Label Z:ClrHome
DelVar STR0
Input "TEXTCODE?",STR0
If STR0=STR9:Then
Goto 0
Else
Goto Q
ClrHome:Goto 0
Label 30:ClrHome:ClrDraw
Disp "F1:VERROUILLER
Disp "F3:AIDE
Disp "F5:QUITTER
Pause :ClrHome
Disp "MODE:PARAMETRES
Disp "APPS:AUTRES
Disp "SUPPR:EFFVARS
Disp "MATH:MATHS
Disp "PRGM:MENU
Pause :Goto 0
Label S:ClrHome
RandInt(1,13->A
RandInt(1,13->B
RandInt(1,13->C
RandInt(1,13->D
RandInt(1,13->E
RandInt(16,24->F
A,10->A
B,10->B
C,10->C
D,10->D
E,10->E
If A=1andB=10
Then
Output(5,3,"BLACKJACK
Pause :Goto S
Else
If B=1andA=10:Then
Output(5,3,"BLACKJACK
Pause :Goto S
End:End
If A=1:Then
B->T
Disp "TOTAL DE
Disp T
Input "1 or 11?",A
If A=1:Then
1->A
Else
11->A
End:End
If B=1:Then
A->T
Disp "TOTAL DE
Disp T
Input "1 or 11?",G
If G=1:Then
1->B
Else
11->B
End:End
ClrHome
A+B->T
Output(1,5,"MAIN
Output(3,1,A
Output(3,4,B
Output(5,3,"TOTAL DE
Output(5,13,T
Output(7,3,"STAY=1 HIT=2
Disp "","","","","","",
If T>21:Goto B
Input G
If G=1:Then
Goto E
Label E:ClrHome
If F>21:Then
Output(3,4,"HOUSE BUST
Output(5,5,"YOU WIN
Pause :Goto 11
End
Output(1,3,"TOTAL DE
Output(2,9,T
Output(4,2,"HOUSE TOTAL DE
Output(5,9,F
If T>F:Then
Output(7,6,"YOU WIN
Pause :Goto 11
End
If F>T:Then
Output(7,5,"YOU LOSE
Pause :Goto 11
End
If F=T:Then
Output(7,4,"EGALITE
Pause :Goto 11
End
Else
If C=1:Then:ClrHome
Disp "TOTAL DE
Disp T
Input "1 or 11?",C
If C=1:Then
1->C
Else
11->C
End:End
A+B+C->T
Disp "","","","","","",
Output(1,5,"MAIN
Output(3,1,A
Output(3,4,B
Output(3,7,C
Output(5,3,"TOTAL DE
Output(5,13,T
Output(7,3,"STAY=1 HIT=2
If T>21:Goto B
Input G
If G=1:Then
Goto E
Else
If D=1:Then:ClrHome
Disp "TOTAL DE
Disp T
Input "1 or 11?",D
If D=1:Then
1->D
Else
11->D
End:End
A+B+C+D->T
Disp "","","","","","",
Output(1,5,"MAIN
Output(3,1,A
Output(3,4,B
Output(3,7,C
Output(3,10,D
Output(5,3,"TOTAL DE
Output(5,13,"STAY=1 HIT=2
If T>21:Goto B
Input G
If G=1:Then
Goto E
Else
If E=1:Then
Disp "TOTAL DE
Disp T
Input "1 or 11?",E
If E=1:Then
1->E
Else
11->E
End:End
A+B+C+D+E->T
Disp "","","","","","",
Output(1,5,"MAIN
Output(3,1,A
Output(3,4,B
Output(3,7,C
Output(3,10,D
Output(3,13,E
Output(5,3,"TOTAL DE
Output(5,13,T
If T>21:Then
Goto B
Else
Pause :Goto E
Label B:ClrHome
Output(1,7,"BUST
Output(3,5,"YOU LOSE
Output(5,3,"TOTAL DE
Output(5,12,T
Pause :Goto 11
Label K:ClrHome:ClrDraw
Disp "ERR:LABEL
Disp "1:QUITTER
DelVar S
Repeat S!=0
getKey->S
If S=105:Goto 99
If S=92:Goto Q
End
If S!=105andS!=92:Goto K
Label 99
Disp "   ECONOMIE     
Disp "
Disp "1:TAUX VARIATION
Disp "
Disp "2:VAR RELAT
Disp "
Disp "3:ELASTICITE
Repeat K!=0
getKey->K
If K=92:Goto T
If K=93:Goto U
If K=94:Goto V
If K=11:Goto Z
If K=15:Goto Q
If K=13:Goto 30
If K=23:Goto 24
If K=42:Goto O
If K=41:Goto M
If K=43:Goto 0
If K=22:Goto 20
If K=44:Goto K
End
Label T:ClrHome:ClrDraw
Input "VAL DEPART=?",D
Input "VAL ARRIVEE=?",A
100->100D/A->X
Text(1,1,"TAUX VARIATION=",X,".
Pause :DelVar X:DelVar A:DelVar D:Goto K
Label U:ClrHome:ClrDraw
Prompt A,D
A-D->X
Text(R,1,"VAR RELAT=",X,".
Pause :DelVar A:DelVar X:DelVar D:Goto K
Label V:ClrHome:ClrDraw
Input "DEMANDE or CONSO=",D
Input "PRIX or REVENU",P
D/P->X
Text(1,1,"ELASTICITE=",X,".
If X<1
Text(11,1,"DEMANDE ELASTIQUE
Pause :DelVar D:DelVar P:DelVar X:Goto K
Label A:ClrHome:ClrDraw
Prompt A,B
gcd(A,B->X
Text(1,1,"PGCD=",X,".
If X=1
Text(6,1,"CES NOMBRES SONT PREMIERS ENTRE EUX
Pause :DelVar A:DelVar B:DelVar X:Goto J
Label C:ClrHome:ClrDraw
Prompt A,B
lcm(A,B->X
Text(1,1,"PPCM=",X,".
Pause :DelVar A:DelVar B:DelVar X:Goto J
Label L:ClrHome
Input X
Disp X
Pause :DelVar X:Goto K
Label H:ClrHome:ClrDraw
Disp "(A+B)^2=
Disp "A^2+2AB+B^2
Pause
Disp "(A-B)^2=
Disp "A^2-2AB+B^2
Pause
Disp "(A+B)(A-B)=
Disp "A^2-B^2
Pause :Goto J
Label J:ClrHome:ClrDraw
Disp "1:REMIDENT
Disp "
Disp "2:CALCUL
Disp "
Disp "3:PRECALCUL
Disp "
Disp "4:STATISTIQUES"
Repeat K!=0
getKey->K
If K=23:Goto 24
If K=42:Goto O
If K=41:Goto M
If K=13:Goto 30
If K=43:Goto 0
If K=11:Goto Z
If K=22:Goto 20
If K=15:Goto Q
If K=92:Goto H
If K=93:Goto L
If K=94:Goto 14
If K=44:Goto K
If K=82:Goto A1
End
Label A1:ClrDraw
FnOff
ê
AxesOn
GridOff
CoordOn
ExprOn
ClrHome
Disp "NB DE DONNEES
Input "PAR AXE:",N
N->dim(L1
N->dim(L2
ClrHome
Disp "ABSCISSES
Input "DEPART:",D
Input "INTERVALLE:",I
D->L1(1)
For(Z,2,N
D+I(Z-1->L1(Z)
End
For(Z,1,N
ClrHome
Disp "ORDONNEES:","VALEUR N[degrees]
Output(2,10,Z
Input P
P->L2(Z
End
Menu(" TYPE GRAPHIQUE ","NUAGE DE POINTS",A2,"COURBE",A3,"HISTOGRAMME",A4,"VALEURS",B2,"QUITTER",Q
Label A2
Menu("     MARQUE     ","€",A5,"[box]",A6,"[dot]",A7
Label A5
Plot1(Scatter,L1,L2,€
ZoomStat
Trace
Pause :Goto J
Label A6
Plot1(Scatter,L1,L2,[box]
ZoomStat
Trace
Pause :Goto J
Label A7
Plot1(Scatter,L1,L2,[dot]
ZoomStat
Trace
Pause :Goto J
Label A3
Menu("     MARQUE     ","€",A8,"[box]",A9,"[dot]",B1
Label A8
Plot1(xyLine,L1,L2,€
ZoomStat
Trace
Pause :Goto J
Label A9
Plot1(xyLine,L1,L2,[box]
ZoomStat
Trace
Pause :Goto J
Label B1
Plot1(xyLine,L1,L2,[dot]
ZoomStat
Trace
Pause :Goto J
Label A4
Plot1(Histogram,L1,L2
L1)->Xmin
max(L1)+I->Xmax
I->Xscl
max(L2)->Ymax
0->Ymin
iPart(Ymax/10)->Yscl
1->c6
DispGraph
Trace
Pause :Goto J
Label B2:ClrHome
1-Var Stats
Pause :Goto J
Label 14:ClrHome
Disp "   PRECALCULS   
Disp "
Disp "1:PGCD
Disp "
Disp "2:PPCM
Disp "
Disp "3:RACINE CARREE
Repeat K!=0
getKey->K
If K=11:Goto Z
If K=13:Goto 30
If K=15:Goto Q
If K=23:Goto 24
If K=42:Goto O
If K=41:Goto M
If K=43:Goto 0
If K=22:Goto 20
If K=92:Goto A
If K=93:Goto C
If K=94:Goto 16
If K=44:Goto K
End
Label 16:ClrHome:ClrDraw
Prompt N
[root]^2N->X
Text(1,1,"RACINE CARREE DE",N,"=",X,".
Pause :Goto 14
Label 15:ClrHome:ClrDraw
Disp "1:THEOREME
Disp "
Disp "2:RECIPROQUE
Repeat K!=0
getKey->K
If K=11:Goto Z
If K=15:Goto Q
If K=13:Goto 30
If K=23:Goto 24
If K=42:Goto O
If K=41:Goto M
If K=43:Goto 0
If K=22:Goto 20
If K=92:Goto 13
If K=93:Goto 12
If K=44:Goto K
End
Label 13:ClrHome
Input "HYPOTENUSE=?",H
Input "COTE 2=?",A
Input "COTE 3=?",B
If 0=H:Then
A^2+B^2->H:[root]^2H->H
ClrHome:Output(1,1,"HYPOTENUSE=",H,".
If 0=A:Then
H^2-B^2->A:[root]^2A->A
ClrHome:Output(1,1,"COTE 2=",A,".
If 0=B:Then
H^2-A^2->B:[root]^2B->B
ClrHome:Output(1,1,"COTE 3=",B,".
End
Pause :DelVar H:DelVar A:DelVar B:Goto 14
Label 12:ClrHome
Input "GRANDE LONGUEUR=",L
Prompt D,E
L^2->L
D^2+E^2->X
If L=X:Then
ClrHome:Output(1,1,"LE TRIANGLE EST RECTANGLE
Else
ClrHome:Output(1,1,"LE TRIANGLE N'EST PAS RECTANGLE
Pause :DelVar L:DelVar E:DelVar D:DelVar X:Goto 14
Label D:ClrHome:ClrDraw
Prompt R
R[pi]^2->A
2[pi]R->P
Text(1,1,"AIRE=",A,".
Text(7,1,"PERIMETRE=",P,".
Pause :DelVar R:DelVar A:DelVar P:Goto I
Label F:ClrHome:ClrDraw
Disp "H=HAUTEUR/BASE
Disp "F=HYP/3[degrees] COTE
Prompt H,F
(H*F)/2->X
Text(1,1,"AIRE=",X,".
Pause :DelVar H:DelVar F:DelVar X:Goto I
Label G:ClrHome:ClrDraw
Prompt A
6A^2->A:A^3->U
Text(1,1,"AIRE=",A,".
Text(7,1,"VOLUME=",V
Pause :DelVar A:DelVar V:Goto I
Label I:ClrHome:ClrDraw
Disp "1:CERCLE
Disp "
Disp "2:TRECTANGLE
Disp "
Disp "3:CUBE
Disp "
Disp "4:PYTHAGORE
Repeat K!=0
getKey->K
If K=11:Goto Z
If K=15:Goto Q
If K=13:Goto 30
If K=23:Goto 24
If K=42:Goto O
If K=41:Goto M
If K=43:Goto 0
If K=22:Goto 20
If K=92:Goto D
If K=93:Goto F
If K=94:Goto G
If K=82:Goto 15
If K=44:Goto K
End
Label P:ClrHome:ClrDraw
"->STR1
"->STR2
GetCalc(STR3
[e](A=[pi])+[pi](A!=[pi]->A
Label P:ClrHome
Menu("     TI-MSN     ","RECEVOIR",R,"ENVOYER",W,"MENU PRINCIPAL",0
Label W
Input "MESSAGE: ",STR3
If A=[pi]:STR3->STR1
If A=[e]:STR3->STR2
Goto M:Label R
If A=[e]:Then
GetCalc(STR1
STR1
Else
GetCalc(STR2
STR2
End
Output(1,1,Ans
Pause :Goto M
Label 11:ClrHome:ClrDraw
Disp "      JEUX     
Disp "
Disp "1:BLACKJACK
Disp "
Disp "2:MORPION
Disp "
Disp "3:SNAKE
Repeat K!=0
getKey->K
If K=11:Goto Z
If K=15:Goto Q
If K=13:Goto 30
If K=23:Goto 24
If K=42:Goto O
If K=41:Goto M
If K=43:Goto 0
If K=22:Goto 20
If K=92:Goto S
If K=93:Goto N
If K=94:Goto 10
If K=44:Goto K
End
Label O:ClrHome:ClrDraw
Disp "     AUTRES   
Disp "
Disp "1:TI-MSN
Disp "
Disp "2:JEUX
Repeat K!=0
getKey->K
If K=44:Goto K
If K=11:Goto Z
If K=15:Goto Q
If K=13:Goto 30
If K=23:Goto 24
If K=42:Goto O
If K=41:Goto M
If K=43:Goto 0
If K=22:Goto 20
If K=92:Goto P
If K=93:Goto 11
End
Label N:ClrHome:ClrDraw
Output(1,7,"!
Output(1,9,"!
Output(2,6,"-+-+-
Output(3,7,"!
Output(3,9,"!
Output(4,6,"-+-+-
Output(5,7,"!
Output(5,9,"!
Output(1,6,"7
Output(1,8,"8
Output(1,10,"9
Output(3,6,"4
Output(3,8,"5
Output(3,10,"6
Output(5,6,"1
Output(5,8,"2
Output(5,10,"3
0->Y
0->Z
0->W
0->T
0->U
0->V
0->O
0->P
0->Q
0->A
0->X
While 1
A->X
getKey->K
If K=92andY=0:Then
If X=1:Then
Output(5,6,"O
A-1->A
1->Y
Else
If X=0:Then
Output(5,6,"X
A+1->A
10->Y
End:End:End
If K=93andZ=0:Then
If X=1:Then
Output(5,8,"O
A-1->A
1->Z
Else
If X=0:Then
Output(5,8,"X
A+1->A
10->Z
End:End:End
If K=94andW=0:Then
If X=1:Then
Output(5,10,"O
A-1->A
1->W
Else
If X=0:Then
Output(5,10,"X
A+1->A
10->W
End:End:End
If K=82andT=0:Then
If X=1:Then
Output(3,6,"O
A-1->A
1->T
Else
If X=0:Then
Output(3,6,"X
A+1->A
10->T
End:End:End
If K=83andU=0:Then
If X=1:Then
Output(3,8,"O
A-1->A
1->U
Else
If X=0:Then
Output(3,8,"X
A+1->A
10->U
End:End:End
If K=84andV=0:Then
If X=1:Then
Output(3,10,"O
A-1->A
1->V
Else
If X=0:Then
Output(3,10,X
A+1->A
10->V
End:End:End
If K=72andO=0:Then
If X=1:Then
Output(1,6,"O
A-1->A
1->O
Else
If X=0:Then
Output(1,6,"X
A+1->A
10->O
End:End:End
If K=73andP=0:Then
If X=1:Then
Output(1,8,"O
A-1->A
1->P
Else
If X=0:Then
Output(1,8,"X
A+1->A
10->P
End:End:End
If K=74andQ=0:Then
If X=1:Then
Output(1,10,"O
A-1->A
1->Q
Else
If X=0:Then
Output(1,10,"X
A+1->A
10->Q
End:End:End
If K=45:Then:ClrHome
Stop:End
If Y+Z+W=3 or T+U+V=3 or O+P+Q=3 or O+U+W=3 or Y+U+Q=3 or O+T+Y=3 or P+U+Z=3 or Q+V+W=3
Then
Output(7,6,"O A GAGNE
Stop:End
If Y+Z+W=30 or T+U+V=30 or O+P+Q=30 or O+U+W=30 or Y+U+Q=30 or O+T+Y=30 or P+U+Z=30 or Q+V+W=30:Then
Output(7,6,"X A GAGNE
Stop:End
If O+P+Q+T+U+V+Y+Z+W=54:Then
Output(7,4,"MATCH NUL
Stop:End
If K=0:Then:End:End
Pause :Goto O
Label M:ClrHome:ClrDraw
Disp "     MATHS     
Disp "
Disp "1:ALGEBRE
Disp "
Disp "2:GEOMETRIE
Repeat K!=0
getKey->K
If K=44:Goto K
If K=11:Goto Z
If K=15:Goto Q
If K=13:Goto 30
If K=23:Goto 24
If K=42:Goto O
If K=41:Goto M
If K=43:Goto 0
If K=22:Goto 20
If K=92:Goto J
If K=93:Goto I
End
Label 0:ClrHome:ClrDraw
Disp "TI-83+.FR ALT OS
Disp "
Disp "1:MATHS
Disp "
Disp "2:AUTRES
Repeat K!=0
getKey->K
If K=44:Goto K
If K=11:Goto Z
If K=15:Goto Q
If K=13:Goto 30
If K=23:Goto 24
If K=42:Goto O
If K=41:Goto M
If K=43:Goto 0
If K=22:Goto 20
If K=92:Goto M
If K=93:Goto O
End
Label 20
ClrHome:ClrDraw
Disp "   PARAMETRES   
Disp "
Disp "1:NOM
Disp " "
Disp "2:EFF VARIABLES
Repeat K!=0
getKey->K
If K=11:Goto Z
If K=15:Goto Q
If K=13:Goto 30
If K=23:Goto 24
If K=44:Goto K
If K=42:Goto O
If K=41:Goto M
If K=43:Goto 0
If K=22:Goto 20
If K=92:Goto 21
If K=93:Goto 24
End
Label 25:ClrHome:ClrDraw
Text(1,1,M
Pause :Goto 0
Label 21:ClrHome:ClrDraw
Disp "      NOM
Disp "   
Disp "1:AFFICHER NOM
Repeat K!=0
getKey->K
If K=11:Goto Z
If K=15:Goto Q
If K=13:Goto 30
If K=44:Goto K
If K=23:Goto 24
If K=42:Goto O
If K=41:Goto M
If K=43:Goto 0
If K=22:Goto 20
If K=92:Goto 22
If K=93:Goto 23
End
Label 22:ClrHome:ClrDraw
Disp "TU T'APPELLES",STR4
Pause :Goto 0
Label 23:ClrHome:ClrDraw
Input "TON NOM?",STR4
Text(1,1,"MODIFICATION EFFECTUEE
Pause :Goto 0
Label 24:ClrHome:ClrDraw
DelVar A:DelVar B:DelVar C:DelVar D:DelVar E:DelVar F:DelVar G:DelVar H:DelVar I:DelVar J:DelVar K:DelVar L:DelVar M:DelVar N:DelVar O:DelVar P:DelVar Q:DelVar R:DelVar S:DelVar T:DelVar U:DelVar V:DelVar W:DelVar X:DelVar Y:DelVar Z:DelVar STR1:DelVar STR2:DelVar STR3:ClrAllLists
Output(1,1,"VARIABLES EFFACEES
Pause :Goto 0
Label 10:ClrHome:ClrDraw
26-2int(2rand->K
{4->L1:Ans->L2:1->I
ClrHome
For(J,1,[e]2
L1(1->L1(J
L2(1->L2(J
Repeat max(S!=L1andAns!=L2
RandInt(1,8->S
RandInt(1,16->T
End
Output(S,Ans,"*
Repeat T=AnsandS=L1(I
getKey
If Ans=45:Goto Q
If Ans=34 or 2>abs(Ans-25:Ans->K
I+1-J(I=J->I
Output(L1(Ans),L2(Ans),"
(K=34)-(K=25)+L1(Ans-(Ans>1
Ans+8(not(Ans)-(Ans=9->L1(I
(K=26)-(K=24)+L2(I-(I>1
Ans+16(not(Ans)-(Ans=17->L2(I
Output(L1(I),Ans,"O
End:End
ClrHome
Label A0:ClrHome
Output(1,1,"ERREUR: FAUSSE CMD
Pause :ClrHome
Output(1,1,"LISEZ L'AIDE F3 SUR LES TOUCHES
Pause :Goto 0
Label Q:ClrHome:ClrDraw:AxesOn
DelVar A:DelVar B:DelVar C:DelVar D:DelVar E:DelVar F:DelVar G:DelVar H:DelVar I:DelVar J:DelVar K:DelVar L:DelVar M:DelVar N:DelVar O:DelVar P:DelVar Q:DelVar R:DelVar S:DelVar T:DelVar U:DelVar V:DelVar W:DelVar X:DelVar Y:DelVar Z:DelVar STR1:DelVar STR2:DelVar STR3:ClrAllLists
Output(1,1,"
No Str4 defined, maybe you should ask the user to input it?
No Str9 defined, maybe you should ask the user to input it?

as I told several times, it has to be defines by the user, and it's in another program, that I can't backup because somebody stole my calculator....

Where are the errors?? And as I said, I'm a beginner, I learnt TI-Basic just 2 months ago!

I know we have to (outside of the program) define Str4 and Str9 as our name and textcode, respectively, but that's not very user-friendly.

Input "USERNAME", Str4
Input "PASSWORD", Str0
Input "TEXTCODE", Str9
If Str0=Str9
//Program Code
End

Scout, it really isn't that big of a deal, in my opinion, if you have to manually input data right now. It's not finished yet and like he said he can't do a whole lot right now so please calm down or be patient for an update.

@Rayquaza
I'm not completely for sure but I do believe all need to be defined to some extent or the calculator will throw a ERR:UNDEFINED. I'm not a hundred percent sure though, I could be wrong.

It's looking quite nice though, keep up the good work

an update will come, this one was the backup (stolen calculator --' ) I have the correct version on my calc which can be very far at the moment

You can program in the PC, in fact, its easier =P

yeah I've seen, but my "parental control??" block wabbit

What the hell?

Google: *name_of_your_parent_control_program* hack disable

okok

Most of those programs are easily hackable and disabled, so good luck!

I discovered I could extract files from TI-Group files   so I've joined PARAMS and UPDTEBCK to this message.
For the moment, I use Cemetech but I can't download any files (from the hacked MP3 to the innocent little README.txt file ) so I'm starting to share the projects, I just need time. I'm not sure if UPDTEBCK works, I never tried it (sorry, I just have one calc ) but PARAMS works, but as I remember, I think I changed little pieces of code. Anyway, I will post the Cemetech links

Yeah, I'm not gonna try to hack my parental control, mainly because yesterday I told my mum my calculator was stolen... 95€ (130USD)

The new release will determine itself whither the username and password are defined or not, with maybe other games added...

[edit]would anyone have the address of an online emulator? I saw one a long time ago, but I don't remember the address :S