Retro computing: Hammurabi - Printable Version

Code:


// Hammurabi

// Converted from a BASIC program in David Ahl's

// "BASIC Computer Games, Microcomputer Edition"

// by Chris Marriott.

//

// Revision history:

// 28 Sep 24: Initial release.



// Constants controlling model behaviour

CONST gameYears:=10;    // number of years to run the model

CONST bushelsPerPerson:=20;  // bushels to feed one person for a year

CONST acresPerPerson:=10;  // acres a person can sow

CONST impeachPercent:=45;  // percentage of deaths triggering impeachment

CONST plaguePercent:=15;    // % probability of plague

CONST STATUS_OK:=0;    // OK to continue

CONST STATUS_QUIT:=1;    // end the game



// Declare variables

population;        // current population

incomers;          // people coming to the city

bushels;          // bushels in the treasury

acres;              // acres owned

acresPlanted;        // acres planted

bushelsFed;          // bushels fed to the people

eaten;              // bushels eaten by rats

harvest;          // bushels harvested

harvestYield;        // bushels per acre harvested

deaths;          // deaths this year

totalDeaths;          // total number of deaths

deathPercent;        // average % deaths

year;              // game year

plague;          // probability of plague

status;          // game status



// Main program



EXPORT Hammurabi()

BEGIN



// Initialise data and display the introductory text

InitData();

Intro();



// Continue until we either reach the time limit, or

// we are impeached.

WHILE year<gameYears AND status==STATUS_OK DO 



  // Display the start of year status

  AnnualReport();



  // Buy or sell land

  BuySellLand();



  // Feed the people

  FeedPeople();



  // Plant crops

  PlantCrops();



  // Harvest time

  HarvestCrops();



  // End of year processing

  YearEnd();



END;



// On a normal exit, display the final year's stats

// and a performance report. If we exited due to being

// impeached, display the impeachment report.

IF status==STATUS_OK THEN

  AnnualReport();

  FinalStatus();

ELSE

  PRINT("\nPress any key to continue...");

  PRINT();

  PRINT("You starved "+deaths+" people in one year!");

  Impeach();

END;



PRINT("\nPress any key to exit.");

RETURN 0;



END;



// Display the introductory screen



Intro()

BEGIN

PRINT();

PRINT("HAMMURABI\n\n");

PRINT("Try your hand at governing ancient Sumeria for");

PRINT("a "+gameYears+"-year term of office. Each year, you must");

PRINT("decide how much land to buy or sell, how much");

PRINT("grain to feed your people, and how much to");

PRINT("plant in the fields. The consequences of failure");

PRINT("are severe!");

PRINT("\nConverted from David Ahl's \"BASIC Computer");

PRINT("Games\" by Chris Marriott.");

PRINT("\nPress any key to begin...");

WAIT();

END;



// Initialise game data



InitData()

BEGIN

status:=STATUS_OK;

year:=0;

population:=95;

deaths:=0;

totalDeaths:=0;

deathPercent:=0;

bushels:=2800;

harvest:=3000;

eaten:=harvest-bushels;

harvestYield:=3;

acres:=harvest/harvestYield;

incomers:=5;

plague:=100; // no plague the first year!

END;



// Display the report for the current year



AnnualReport()

BEGIN



// Increment the year

year:=year+1;



PRINT();

PRINT("Hammurabi, I beg to report to you,");

PRINT("In year "+year+", "+deaths+" people starved, "+incomers+" came to the city.");



population:=population+incomers;



// If the plague has struck, halve the population

IF plague<plaguePercent THEN

  population:=FLOOR(population/2);

  PRINT("A horrible plague struck! Half the people died.");

END;



PRINT("Population is now "+population);

PRINT("The city now owns "+acres+" acres.");

PRINT("You harvested "+harvestYield+" bushels per acre.");

PRINT("Rats ate "+eaten+" bushels.");

PRINT("You now have "+bushels+" bushels in store.");

PRINT("\n");

END;



// Buy or sell land



BuySellLand()

BEGIN

LOCAL landPrice, trade, totalCost;  



// Generate the price of land this year

landPrice:= RANDINT(17,26);



// Do we want to buy land?

REPEAT

  PRINT("Land is trading at "+landPrice+" bushels per acre.");

  PRINT("How many acres do you wish to buy?");

  trade:=ReadNum();

  totalCost:=landPrice*trade;

  IF totalCost>bushels THEN

    TooExpensive();

  END;

UNTIL totalCost<=bushels;



IF trade<>0 THEN

  acres:=acres+trade;

  bushels:=bushels-totalCost;



// If we haven't bought land, do we want to sell?

ELSE

  REPEAT

    PRINT("How many acres do you wish to sell?");

    trade:=ReadNum();

    IF trade>acres THEN

      TooMuchLand();

    END;

  UNTIL trade<=acres;

  acres:=acres-trade;

  bushels:=bushels+landPrice*trade;

END;

END;



// Decide how much grain to feed the people

FeedPeople()

BEGIN

REPEAT

  PRINT("How many bushels do you wish to feed your people?");  

  bushelsFed:=ReadNum();

  IF bushelsFed>bushels THEN

    TooExpensive();

  END

UNTIL bushelsFed<=bushels;

bushels:=bushels-bushelsFed;

END;



// Decide how many acres to plant



PlantCrops()

BEGIN

LOCAL OK;



REPEAT

  OK:=1;

  PRINT("How many acres do you wish to plant with seed?");

  acresPlanted:=ReadNum();



  // More acres that you own?

  IF acresPlanted>acres THEN

    TooMuchLand();

    OK:=0;

  END;



  // Enough grain for seed?

  IF OK==1 AND FLOOR(acresPlanted/2)>bushels THEN

    TooExpensive();

    OK:=0;

  END;



  // Enough people to tend the crops?

  IF OK==1 AND acresPlanted>acresPerPerson*population THEN

    PRINT("But you only have "+population+" people to tend the fields! Now then,");

    OK:=0;

  END;



UNTIL OK==1;



// Remove the planted grain from the treasury

bushels:=bushels-FLOOR(acresPlanted/2);



END;



// Harvest this year's crops



HarvestCrops()

BEGIN

LOCAL rnd;



// Random harvest yield

harvestYield:=RANDINT(1,5);

harvest:=acresPlanted*harvestYield;



// Rats?

rnd:=RANDINT(1,5);

IF FLOOR(rnd/2)==rnd/2 THEN

  eaten:=FLOOR(bushels/rnd);

ELSE

  eaten:=0;  

END;



bushels:=bushels-eaten+harvest;



END;



// End of year processing



YearEnd()

BEGIN

LOCAL peopleFed, rnd;



// How many people have come to the city?

rnd:=RANDINT(1,5);

incomers:=FLOOR(rnd*(20*acres+bushels)/population/100+1);



// How many people had full tummies?

peopleFed:=FLOOR(bushelsFed/bushelsPerPerson);



// Calculate the probability of plague.

plague:=RANDOM(0,100);



// If the population is greater than the number of people

// fed, people will starve

IF population>peopleFed THEN

  deaths:=population-peopleFed;

  IF deaths>impeachPercent/100*population THEN

    status:=STATUS_QUIT;

  END;

  deathPercent:=((year-1)*deathPercent+deaths*100/population)/year;

  population:=peopleFed;

  totalDeaths:=totalDeaths+deaths;

ELSE

  // We've fed everyone

  deaths:=0;

END;



END;



// Final status report



FinalStatus()

BEGIN

LOCAL acrespp, summary;

PRINT("\nPress any key to continue...");

WAIT();

PRINT();

PRINT("In your term of office, "+FLOOR(deathPercent)+"% of the population starved on average.");

PRINT("A total of "+totalDeaths+" people died!");

acrespp:=acres/population;

PRINT("You started with 10 acres per person and ended with "+FLOOR(acrespp)+" acres per person.");



summary:=0;

IF deathPercent>33 OR acrespp<7 THEN

  Impeach();

  summary:=1;

END;

IF summary==0 AND (deathPercent>10 OR acrespp<9) THEN

  PRINT("Your heavy-handed performance smacks of Nero and Ivan IV. The people (remaining) find you an unpleasant ruler and, frankly, hate your guts!");

  summary:=1; 

END;

IF summary==0 AND acrespp<10 THEN

  PRINT("Your performance could have been somewhat better, but really wasn't too bad at all. "+FLOOR(population*0.8*RANDOM())+" people would dearly like to see you assassinated, but we all have our trivial problems.");

  summary:=1;

END;

IF summary==0 THEN

  PRINT("A fantastic performance! Charlemagne, Disraeli and Jefferson combined could not have done better!");

END;

 

END;



// You've been impeached



Impeach()

BEGIN

PRINT("Due to this extreme mismanagement you have not only been impeached and thrown out of office, but you have also been declared a national disgrace!");

END;



// Not enough grain to do this



TooExpensive()

BEGIN

PRINT("Hammurabi, think again! You have only "+bushels+" bushels. Now then,");

END;



// Not enough land to do this



TooMuchLand()

BEGIN

PRINT("Hammurabi, think again! You own only "+acres+" acres. Now then,");

END;



// Read a line from the terminal, echo the input, and return a numeric value



ReadNum()

BEGIN

LOCAL input;

input:=READLINE();

PRINT(input);

RETURN EXPR(input);

END;