Article: 2407 of rec.puzzles From: steed@dcs.qmw.ac.uk (Anthony Steed) Subject: Tough Puzzle: Alphacipher Organization: Computer Science Dept, QMW, University of London Date: Wed, 24 Mar 1993 12:23:21 GMT In England there is a magazine called Tough Puzzles full of various devious types of logic problem. There's one type that has me stumped for a simple and short method to get a handle on the solution, my methods lead to reams and reams of scribbled notes. Here's a sample, does anyone have a bright idea, about how it _should_ be done? Alphacipher The numbers 1 - 26 have been randomly assigned to the letters of the alphabet. The numbers beside each word are the total of the values assigned to the letters in the word. e.g for LYRE L,Y,R,E might equal 5,9,20 and 13 respectively or any other combination that add up to 47. The problem - What is the value of D ? BALLET 45 POLKA 59 CELLO 43 QUARTET 50 CONCERT 74 SAXOPHONE 134 FLUTE 30 SCALE 51 FUGUE 50 SOLO 37 GLEE 66 SONG 61 JAZZ 58 SOPRANO 82 LYRE 47 THEME 72 OBOE 53 VIOLIN 100 OPERA 65 WALTZ 34 Anthony Steed - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - S P O I L E R - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Article: 2416 of rec.puzzles From: grabiner@math.harvard.edu (David Grabiner) Date: 24 Mar 93 21:34:59 GMT Anthony Steed writes: > Alphacipher > The numbers 1 - 26 have been randomly assigned to the letters of the > alphabet. The numbers beside each word are the total of the values > assigned to the letters in the word. e.g for LYRE L,Y,R,E might equal > 5,9,20 and 13 respectively or any other combination that add up to 47. > The problem - What is the value of D ? > BALLET 45 POLKA 59 > CELLO 43 QUARTET 50 > CONCERT 74 SAXOPHONE 134 > FLUTE 30 SCALE 51 > FUGUE 50 SOLO 37 > GLEE 66 SONG 61 > JAZZ 58 SOPRANO 82 > LYRE 47 THEME 72 > OBOE 53 VIOLIN 100 > OPERA 65 WALTZ 34 For anyone who wants to check answers without much of a spoiler, the value of CHORD follows. CHORD is 67. A full solution follows another page break. Spoiler warning... Subtracting one word from another gives the following equations: a.NG-LO=24 b.GU-LT=20 c.SA-LO=8 d.SON-E=17 e.CAE-OO=14 f.GE-CLO=23 We can now derive these: g.CN-E=1 (a-f) h.SO-C=16 (d-g) i.LOO-AC=8 (h-c) j.EL=22 (e+i) k.G-L=22 (GLEE-2j) l.T-U=2 (k-b) m.FUT=8 (FLUTE-j) The only sets which sum to 8 are 1,2,5 and 1,3,4, so the only way to satisfy l and m is F=4, T=3, U=1. Since L is at most 4 by k, L=2, and thus G=24, E=20. Taking what remains of some words: BA=18 CO=19 OBO=33 SCA=29 SOO=35 SON=37 Now it is easier to see how to proceed. We have S-B=2, and thus BCA=27. This gives C=9 since BA=18; thus O=10, B=13, A=5, S=15, N=12, and now we can get several other letters by substitution. CONCET=63 so R=11 LRE=33 so Y=14 OERA=46 so P=19 POLA=36 so K=23 UARTET=43 so Q=7 The remaining words become: JZZ=53 XH=43 HM=29 VII=76 WZ=24 VII=76 must be 26+25+25. X-M=14, and 22 and 8 are the only remaining pair; thus H=21. JZZ=53 can now only be 17+18+18, and thus W=6. 1 2 3 4 5 6 7 8 9 10 11 12 13 U L T F A W Q M C O R N B 14 15 16 17 18 19 20 21 22 23 24 25 26 Y S J Z P E H X K G I V This leaves D=16. -- David Grabiner, grabiner@zariski.harvard.edu "We are sorry, but the number you have dialed is imaginary." "Please rotate your phone 90 degrees and try again." Disclaimer: I speak for no one and no one speaks for me. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Article 2460 of rec.puzzles: From: lbaum@atc.boeing.com (Larry Baum) Date: Fri, 26 Mar 1993 00:58:48 GMT Anthony Steed writes: >Alphacipher >The numbers 1 - 26 have been randomly assigned to the letters of the alphabet. >The numbers beside each word are the total of the values assigned to the >letters in the word. e.g for LYRE L,Y,R,E might equal 5,9,20 and >13 respectively or any other combination that add up to 47. > >The problem - What is the value of D ? > > >BALLET 45 POLKA 59 >CELLO 43 QUARTET 50 >CONCERT 74 SAXOPHONE 134 >FLUTE 30 SCALE 51 >FUGUE 50 SOLO 37 >GLEE 66 SONG 61 >JAZZ 58 SOPRANO 82 >LYRE 47 THEME 72 >OBOE 53 VIOLIN 100 >OPERA 65 WALTZ 34 The trick is to analyze the letter patterns and look for close matches; so after a bit of study we see: SOPRANO = 82 SON + OPERA = 82 + E SON = 17 + E SONG = 17 + GE 44 = GE FUU = FUGUE - GE = 6 So F = 4, U = 1 LE = GLEE - GE = 22 From FLUTE, T = 3 Also LE = 22 & GE = 44 => G = L + 22 So G = 24, L = 2 (since 1, 3 and 4 are used) From FUGUE, E = 20 From OBOE, BOO = 33 From SOLO, SOO = 35 => S = B + 2 From BALLET, BA = 18 => SA = 20 From SCALE, SCA = 29 So C = 9 From CELLO, O = 10 From OBOE, B = 13 From SOLO, S = 15 From SCALE, A = 5 From SONG, N = 12 From CONCERT, R = 11 From LYRE, Y = 14 From OPERA, P = 19 From POLKA, K = 23 From, QUARTET, Q = 7 From VIOLIN, VII = 76 => either V = 24 (but G=24) or V = 26 So, V = 26 I = 25 Our remaining letters are: D H J M W X Z Our remaining numbers are: 6 8 16 17 18 21 22 From THEME, HM = 29 => H,M are 8,21 in some order From SAXOPHONE, XH = 43 => X,H are 21,22 in some order So H = 21 M = 8 X = 22 From JAZZ, JZZ = 53 => J is odd. 17 is the only odd number left; So J = 17 Z = 18 From WALTZ, W = 6 So D = 16 by elimination! To recap: A B C D E F G H I J K L M 5 13 9 16 20 4 24 21 25 17 23 2 8 N O P Q R S T U V W X Y Z 12 10 19 7 11 15 3 1 26 6 22 14 18 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Article: 2736 of rec.puzzles From: imc@comlab.ox.ac.uk (Ian Collier) Date: 28 Mar 93 14:42:22 GMT Warning: this is *not* a "nice" solution... Spoiler: Well, I used a program to transform the above mechanically into 20 simultaneous equations, added "D=const, H=const, I=const, J=const, K=const, L=const" to make 26 non-singular simultaneous equations in 26 unknowns with 6 unknowns on the right-hand side, and used Matlab to obtain 26 equations of the form A = -38 + 3K - 13L B = 37 - 2K + 11L ... Z = 48 - .5J - 1.5K + 6.5L by inverting the matrix of coefficients (the choice of HIJKL as unknowns in the above was arbitrary, except that my first choice of ABCEF made the equations singular). Then, noting that the equation for A guarantees L<4 and K>(38+13L)/3, I wrote a program to search the solution space in K and L for one in which no number was duplicated or out of range, ignoring all the letters that depend on H, I or J. Fortunately, only one solution (K=23, L=2) resulted. I amended the program to search the resulting space for values of J, and found two solutions (17 or 21). It was easy enough to finish off by hand. A=5 B=13 C=9 D=16 E=20 F=4 G=24 H=21 I=25 J=17 K=23 L=2 M=8 N=12 O=10 P=19 Q=7 R=11 S=15 T=3 U=1 V=26 W=6 X=22 Y=14 Z=18 The value of D is 16. Ian Collier Ian.Collier@prg.ox.ac.uk | imc@ecs.ox.ac.uk - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -