//
// Note: this is a model answer
//       other answers are possible
//

[ex2a() : Problem 
 -> let pb := makeProblem("home truths",20),
        // workmen
        AndyMann    := makeIntVar(pb,"Andy Mann",1,5),
        BrettSaw    := makeIntVar(pb,"Brett Saw",1,5),
        DrewScriver := makeIntVar(pb,"Drew Scriver",1,5),
        GeorgeClamp := makeIntVar(pb,"George Clamp",1,5),
        SteveDawe   := makeIntVar(pb,"Steve Dawe",1,5),
        // problems
        BurstPipe   := makeIntVar(pb,"Burst Pipe",1,5),
        Fused       := makeIntVar(pb,"Fused Electrics",1,5),
        Injured     := makeIntVar(pb,"Injured Himself",1,5),
        OverSpent   := makeIntVar(pb,"Over spent",1,5),
        Ruined      := makeIntVar(pb,"Ruined Carpet",1,5),
        // rooms
        Bathroom    := makeIntVar(pb,"Bathroom",1,5),
        Bedroom     := makeIntVar(pb,"Bedroom",1,5),
        Kitchen     := makeIntVar(pb,"Kitchen",1,5),
        Roof        := makeIntVar(pb,"Roof",1,5),
        Windows     := makeIntVar(pb,"Windows",1,5),
        // months
        Feb         := makeIntVar(pb,"February",1,5),
        Mar         := makeIntVar(pb,"March",1,5),
        Jun         := makeIntVar(pb,"June",1,5),
        Sep         := makeIntVar(pb,"September",1,5),
        Nov         := makeIntVar(pb,"November",1,5)
     in (post(pb,allDifferent(list(AndyMann,BrettSaw,DrewScriver,GeorgeClamp,SteveDawe))),
         post(pb,allDifferent(list(BurstPipe,Fused,Injured,OverSpent,Ruined))),
         post(pb,allDifferent(list(Feb,Mar,Jun,Sep,Nov))),
         post(pb,allDifferent(list(Bathroom,Bedroom,Kitchen,Roof,Windows))),
         post(pb,GeorgeClamp !== Nov),
         post(pb,GeorgeClamp == OverSpent),
         post(pb,GeorgeClamp == Roof),
         post(pb,Nov !== BurstPipe),
         post(pb,BurstPipe == Kitchen),
         post(pb,SteveDawe == Jun),
         post(pb,BrettSaw == Injured),
         post(pb,DrewScriver !== Windows),
         post(pb,DrewScriver !== Fused),
         post(pb,Fused == Sep),
         post(pb,Bathroom == Mar),
         post(pb,Ruined == Bedroom),
         pb)]

//
// Page 48, Issue 32
//
// q1: answer the basic question
//     give performance statistics 
// q2: there are 120 solutions 
// q3: we can permute the 5 values, therefore 5! solutions  
// q4: use smallest domain first, or brelaz or dom/deg. Explain
//     how the heuristic works
// q5: 20 variables (n = 20) each with 5 values (m = 5)
//     therefore 5^20
//