58 lines
1.2 KiB
C++
58 lines
1.2 KiB
C++
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#include <iostream>
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#include <vector>
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#include <cmath>
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#include <random>
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std::vector<float> ages;
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std::vector<int> balances;
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const int N = 10000;
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const int DURATION = 1000;
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const int MAX_AGE = 100;
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const int LOGISTIC_CARRYING_CAPACITY = 100000;
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const int LOGISTIC_GROWTH_RATE = 1;
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const int LOGISTIC_MIDPOINT = DURATION / 2;
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// state mutation funcs
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void transfer_balance(int from, int to, int balance) {
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balances[from] -= balance;
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balances[to] += balance;
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}
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void kill_even_redist(int id) {
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ages.erase(ages.begin()+id);
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balances.erase(balances.begin()+id);
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}
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void kill_inheritance(int id) {
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ages.erase(ages.begin()+id);
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balances.erase(balances.begin()+id);
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}
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void frame_quarter() {
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for (int i = 0; i < ages.size(); i++) {
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ages[i] += 1;
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if (ages[i] > MAX_AGE) {
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kill_inheritance(i);
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}
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}
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}
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// modeling functions
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float logistic_func(int year) {
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// https://en.wikipedia.org//wiki/Logistic_function
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return LOGISTIC_CARRYING_CAPACITY / (1 + (-LOGISTIC_GROWTH_RATE * exp(year - LOGISTIC_MIDPOINT)));
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}
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int main() {
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// init state
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for (int i = 0; i < 1000; i++) {
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std::cout << logistic_func(i) << std::endl;
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}
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return 0;
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}
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