Question

Rules of the leprechaun world

The game starts out with n leprechauns. Each leprechaun starts out with a million dollars of gold (i.e., gi = 1,000,000). The player wants to trap as many of these leprechauns in a pit and steal their gold! The leprechauns are all in a row, with each leprechaun at location xi, a double precision floating point number. Initially, the first leprechaun is at x=0, the second at x=1000, the third at 2000, ...; i.e., xi = i*1000, i=0,1,2,....
At every iteration of the simulation, the leprechauns are processed in strict order from i=0,1,2,... The processing of a leprechaun involves these steps:

1. The leprechaun jumps to a new location xi + r * gi, where r is a random number between -1 and 1.

2. There is a pit located between -1,000 and 1,000. If -1000 < xi < 1000, then that leprechaun is trapped forever (does not participate in the game anymore) and all his gold is added to the player’s score (the player starts with score=0).

3. If a leprechaun lands right on top of another (k), then the newly arrived leprechaun steals all the gold from k, and the bankrupt leprechaun k exits the game.

4. The leprechaun then steals half the gold from the nearest leprechauns to his right and left, if he indeed has both neighbours. (If the position moved to is either the largest or smallest value of all xi, then there is only one neighbour that is nearest. In this case he steals half the gold from this nearest neighbour).

The game ends after a fixed period of time (e.g., 20 seconds), at which point the final score is displayed.

Program input

The program initially asks the user for:

A number to initialize the random number generator (that dictates the jumping of the leprechauns)

The number of leprechauns

Game play time, i.e., time to run the simulation in seconds

Program output

At every iteration, only these events should be printed out:

The trapping of a leprechaun in a pit (results in a score increase)

Landing exactly on another leprechaun

At the end of the simulations, print out:

The number of iterations completed

The number of leprechauns trapped in the pit

The score

The following code is the skeleton we were supposed to use with our additions made in bold, but we need help making sure we are doing our code correctly and inputting step #4:

(We are supposed to use a MAP for the project)

#include <iostream>
#include <chrono>
#include <random>
#include <map>
#include <vector>

using namespace std;

class RandomNumberGenerator {
public:
   RandomNumberGenerator(int x) :generator(x) {};
   // return a double between -1 and 1
   double randomBetween1and2() {
       return (2.0*generator()) / generator.max() - 1.0;
   }
private:
   minstd_rand0 generator;
};

int N;
// Use a constant random number seed so behavior is consistent from run to run.
int RANDOM_SEED;

int main()
{

   cout << "Enter seed for random number generator: ";
   cin >> RANDOM_SEED;
   RandomNumberGenerator rng(RANDOM_SEED);

   cout << "Enter number of leprechauns: ";
   cin >> N;

   long playtime;
   cout << "Enter game play time (seconds): ";
   cin >> playtime;
   playtime = playtime * 1000; // convert to milliseconds

   double score = 0;
   int nTrapped = 0;

//
   // CODE FOR INITIALIZING DATA STRUCTURES GOES HERE

   multimap<int, int> DataStructure;
   int gold = 1000000;
   for (int i = 0; i < N; i++)
   {
       //Create N-locations based on the amount of leprechauns.
       //Key: Location Value: What leprechaun is present.
       double location = i * gold;
       DataStructure.insert(make_pair(location, i + 1));
   }
   //Iterator to traverse around leprechauns:

   //Vector for Gold:
   //Creates N ints with default value of gold(1mil)
   vector<double>LeprechaunGold(N, gold);

   int t = 0; // keep track of number of iterations
   auto start_time0 = chrono::high_resolution_clock::now();
   auto timeSinceStartMS = 0;
   do {
       // CODE FOR A SINGLE ITERATION GOES HERE

       //Iteration - Traverse through the data structure:
       for (std::multimap<int, int>::iterator it = DataStructure.begin(); it != DataStructure.end(); ++it)
       {
           int vectorIterator = 0;
           //1 The leprechaun jumps to a new location.
          //// You can use the random number generator like so:
           double r = rng.randomBetween1and2();
          double x = 0;
           x = x + r*gold;
           DataStructure.insert(make_pair(x, (*it).second));
           //Delete old location.
           DataStructure.erase(it);
           //2 Determine if Key is inbetween pit.
           if (x >= -1000 || x <= 1000)
          {
               //If it IS between -1000 and 1000(It's in the PIT. "I fell in the pit. You fell in the pit. We all were in the pit.... THE PIT.")
               //Delete this leprechaun AND put goldVector(of that leprechaun) to 0, and place gold into score.
               DataStructure.erase(it);
               score += LeprechaunGold[vectorIterator];
               LeprechaunGold[vectorIterator] = 0;

           }
           //3 Determine if multiple keys(multiple leprechauns in one spot)
           //Count X.
           if (DataStructure.count(x) >= 1)
           {
               //If there are greater than one, two leprechauns are occupying the same spot(same key)
               std::multimap<int, int>::iterator toBeDeleted = DataStructure.find(x);
              

               /*range = DataStructure.equal_range(x);
               for (it = range.first; it != range.second; ++it)
               {

               }*/
           }

          //4 Leprechaun steals half gold from neighbor(s)

           //Move to next leprechaun in Goldvector:
           vectorIterator++;
       }
       t++;
       // code to measure run time
       auto end_time = std::chrono::high_resolution_clock::now();
       auto timeSinceStart = end_time - start_time0;
       timeSinceStartMS = chrono::duration_cast<chrono::milliseconds>(timeSinceStart).count();
   } while (timeSinceStartMS < playtime);

   cout << "Number of iterations = " << t << endl;
   cout << "Number of trapped leprechauns = " << nTrapped << endl;
   cout << "Score = " << (long)score << endl;
   return 0;
}