Einstein's puzzle (System Verilog) solved by Incisive92

Hello All,

Following is the einstein's puzzle solved by cadence Incisive92  (solved in less than 3 seconds -> FAST!!!!!!)

Thanks,

Vinay Honnavara

Verification engineer at Keyu Tech

vinayh@keyutech.com

 // Author: Vinay Honnavara

// Einstein formulated this problem : he said that only 2% in the world can solve this problem
// There are 5 different parameters each with 5 different attributes
// The following is the problem

// -> In a street there are five houses, painted five different colors (RED, GREEN, BLUE, YELLOW, WHITE)

// -> In each house lives a person of different nationality (GERMAN, NORWEGIAN, SWEDEN, DANISH, BRITAIN)

// -> These five homeowners each drink a different kind of beverage (TEA, WATER, MILK, COFFEE, BEER),

// -> smoke different brand of cigar (DUNHILL, PRINCE, BLUE MASTER, BLENDS, PALL MALL)

// -> and keep a different pet (BIRD, CATS, DOGS, FISH, HORSES)


///////////////////////////////////////////////////////////////////////////////////////
// *************** Einstein's riddle is: Who owns the fish? ***************************
///////////////////////////////////////////////////////////////////////////////////////

/*
Necessary clues:

1. The British man lives in a red house.
2. The Swedish man keeps dogs as pets.
3. The Danish man drinks tea.
4. The Green house is next to, and on the left of the White house.
5. The owner of the Green house drinks coffee.
6. The person who smokes Pall Mall rears birds.
7. The owner of the Yellow house smokes Dunhill.
8. The man living in the center house drinks milk.
9. The Norwegian lives in the first house.
10. The man who smokes Blends lives next to the one who keeps cats.
11. The man who keeps horses lives next to the man who smokes Dunhill.
12. The man who smokes Blue Master drinks beer.
13. The German smokes Prince.
14. The Norwegian lives next to the blue house.
15. The Blends smoker lives next to the one who drinks water.
*/




typedef enum bit [2:0]  {red, green, blue, yellow, white} house_color_type;
typedef enum bit [2:0]  {german, norwegian, brit, dane, swede} nationality_type;
typedef enum bit [2:0]  {coffee, milk, water, beer, tea} beverage_type;
typedef enum bit [2:0]  {dunhill, prince, blue_master, blends, pall_mall} cigar_type;
typedef enum bit [2:0]  {birds, cats, fish, dogs, horses} pet_type;




class Einstein_problem;

    rand house_color_type house_color[5];
    rand nationality_type nationality[5];
    rand beverage_type beverage[5];
    rand cigar_type cigar[5];
    rand pet_type pet[5];
        rand int arr[5];
    
    constraint einstein_riddle_solver {
    
        
    
        foreach (house_color[i])
            foreach (house_color[j])
               if (i != j)
                house_color[i] != house_color[j];
        foreach (nationality[i])
            foreach (nationality[j])
               if (i != j)
                nationality[i] != nationality[j];
        foreach (beverage[i])
            foreach (beverage[j])
               if (i != j)
                beverage[i] != beverage[j];
        foreach (cigar[i])
            foreach (cigar[j])
               if (i != j)
                cigar[i] != cigar[j];
        foreach (pet[i])
            foreach (pet[j])
               if (i != j)
                pet[i] != pet[j];
    
    
        //1) The British man lives in a red house.
        foreach(nationality[i])
                (nationality[i] == brit) -> (house_color[i] == red);
                
        
        //2) The Swedish man keeps dogs as pets.
        foreach(nationality[i])
                (nationality[i] == swede) -> (pet[i] == dogs);
                
                
        //3) The Danish man drinks tea.        
        foreach(nationality[i])
                (nationality[i] == dane) -> (beverage[i] == tea);
        
        
        //4) The Green house is next to, and on the left of the White house.
        foreach(house_color[i])        
                 if (i<4)
                    (house_color[i] == green) -> (house_color[i+1] == white);
        
        
        //5) The owner of the Green house drinks coffee.
        foreach(house_color[i])
                (house_color[i] == green) -> (beverage[i] == coffee);
                
        
        //6) The person who smokes Pall Mall rears birds.
        foreach(cigar[i])
                (cigar[i] == pall_mall) -> (pet[i] == birds);
        
        
        //7) The owner of the Yellow house smokes Dunhill.
        foreach(house_color[i])
                (house_color[i] == yellow) -> (cigar[i] == dunhill);
        
        
        //8) The man living in the center house drinks milk.
        foreach(house_color[i])
                if (i==2) // i==2 implies the center house (0,1,2,3,4) 2 is the center
                    beverage[i] == milk;
        
        
        
        //9) The Norwegian lives in the first house.
        foreach(nationality[i])        
                if (i==0) // i==0 is the first house
                    nationality[i] == norwegian;
        
        
        
        //10) The man who smokes Blends lives next to the one who keeps cats.
        foreach(cigar[i])        
                if (i==0) // if the man who smokes blends lives in the first house then the person with cats will be in the second
                    (cigar[i] == blends) -> (pet[i+1] == cats);
        
        foreach(cigar[i])        
                if (i>0 && i<4) // if the man is not at the ends he can be on either side
                    (cigar[i] == blends) -> (pet[i-1] == cats) || (pet[i+1] == cats);
        
        foreach(cigar[i])        
                if (i==4) // if the man is at the last
                    (cigar[i] == blends) -> (pet[i-1] == cats);
        
        foreach(cigar[i])        
                if (i==4)
                    (pet[i] == cats) -> (cigar[i-1] == blends);
        
        
        //11) The man who keeps horses lives next to the man who smokes Dunhill.
        foreach(pet[i])
                if (i==0) // similar to the last case
                    (pet[i] == horses) -> (cigar[i+1] == dunhill);
        
        foreach(pet[i])        
                if (i>0 & i<4)
                    (pet[i] == horses) -> (cigar[i-1] == dunhill) || (cigar[i+1] == dunhill);
                    
        foreach(pet[i])        
                if (i==4)
                    (pet[i] == horses) -> (cigar[i-1] == dunhill);
                    


        //12) The man who smokes Blue Master drinks beer.
        foreach(cigar[i])
                (cigar[i] == blue_master) -> (beverage[i] == beer);
        
        
        //13) The German smokes Prince.
        foreach(nationality[i])        
                (nationality[i] == german) -> (cigar[i] == prince);
        

        //14) The Norwegian lives next to the blue house.
        foreach(nationality[i])
                if (i==0)
                    (nationality[i] == norwegian) -> (house_color[i+1] == blue);
        
        foreach(nationality[i])        
                if (i>0 & i<4)
                    (nationality[i] == norwegian) -> (house_color[i-1] == blue) || (house_color[i+1] == blue);
        
        foreach(nationality[i])        
                if (i==4)
                    (nationality[i] == norwegian) -> (house_color[i-1] == blue);
        

        //15) The Blends smoker lives next to the one who drinks water.            
        foreach(cigar[i])            
                if (i==0)
                    (cigar[i] == blends) -> (beverage[i+1] == water);
        
        foreach(cigar[i])        
                if (i>0 & i<4)
                    (cigar[i] == blends) -> (beverage[i-1] == water) || (beverage[i+1] == water);
                    
        foreach(cigar[i])        
                if (i==4)
                    (cigar[i] == blends) -> (beverage[i-1] == water);
        
    } // end of the constraint block
    


    // display all the attributes
    task display ;
        foreach (house_color[i])
            begin
                $display("HOUSE : %s",house_color[i].name());
            end
        foreach (nationality[i])
            begin
                $display("NATIONALITY : %s",nationality[i].name());
            end
        foreach (beverage[i])
            begin
                $display("BEVERAGE : %s",beverage[i].name());
            end
        foreach (cigar[i])
            begin
                $display("CIGAR: %s",cigar[i].name());
            end
        foreach (pet[i])
            begin
                $display("PET : %s",pet[i].name());
            end
        foreach (pet[i])
            if (pet[i] == fish)
                $display("THE ANSWER TO THE RIDDLE : The %s has %s ", nationality[i].name(), pet[i].name());
    
    endtask // end display
    
    
endclass




program main ;

    initial
        begin
            Einstein_problem ep;
            ep = new();
            if(!ep.randomize())
                $display("ERROR");
            ep.display();
        end
endprogram // end of main