Added Growing Annuity (in Cash Flows) implementing both the closed fo…

…rmula as well as the looping method

growingannuity.cpp

@@ -0,0 +1,90 @@
+#include <iostream>
+#include <iomanip>
+#include <cmath>
+#include <chrono>
+#include <stdio.h>
+#include <Windows.h>
+
+using namespace std;
+
+#define PERCENTILE 100
+
+enum inputs {
+    FIXED_AMOUNT = 1,
+    FIXED_INTEREST_RATE = 2,
+    FIXED_GROWTH_RATE = 3,
+    FIXED_TIME = 4,
+};
+
+class GrowingAnnuity {
+    public:
+        double fixed_amount;
+        double fixed_interest_rate;
+        double fixed_growth_rate;
+        int fixed_time;
+};
+
+void printGrowingAnnuityDetails(GrowingAnnuity a) {
+    cout << setfill(' ') << fixed << setprecision(2);
+    cout << "                 ======================================" << endl;
+    cout << "                 ||  GROWING ANNUITY (IN CONTRACTS)  ||" << endl;
+    cout << "                 ======================================" << endl;
+    cout << "                     [INTEREST RATE IN PERCENTILE]" << endl;
+    cout << "\n";
+    cout << setw(15) << "FIXED AMOUNT" << setw(25) << "FIXED INTEREST RATE" << setw(25) << "FIXED GROWTH RATE" << setw(25) << "FIXED TIME IN YEARS" << endl;
+    cout << setw(15) << a.fixed_amount << setw(25) << a.fixed_interest_rate << setw(25) << a.fixed_growth_rate << setw(25) << a.fixed_time << endl;
+}
+
+void closedFormGrowingAnnuity(GrowingAnnuity a) {
+    auto begin = chrono::high_resolution_clock::now();
+
+    cout << "\nCLOSED FORM GROWING ANNUITY: ";
+    double cfga = 0.0;
+    a.fixed_interest_rate /= PERCENTILE;
+    a.fixed_growth_rate /= PERCENTILE;
+    cfga =  (a.fixed_amount / (a.fixed_interest_rate - a.fixed_growth_rate)) * (1 - pow(1 + a.fixed_growth_rate, a.fixed_time) / pow(1 + a.fixed_interest_rate, a.fixed_time));
+    cout << cfga << endl;
+
+    auto end = chrono::high_resolution_clock::now();
+    auto elapsed = chrono::duration_cast<std::chrono::nanoseconds>(end - begin);
+    cout << "EXECUTED IN: " << elapsed.count() * (1e-6) << " ms" << endl;
+
+    cout << "\n";
+}
+
+void loopFormGrowingAnnuity(GrowingAnnuity a) {
+    auto begin = chrono::high_resolution_clock::now();
+
+    cout << "LOOP FORM GROWING ANNUITY: ";
+    double lfga = 0.0;
+    a.fixed_interest_rate /= PERCENTILE;
+    a.fixed_growth_rate /= PERCENTILE;
+    for(int i = 1; i <= a.fixed_time; i++) {
+        lfga += a.fixed_amount * pow(1 + a.fixed_growth_rate, i - 1) / pow(1 + a.fixed_interest_rate, i);
+    }
+    cout << lfga << endl;
+
+    auto end = chrono::high_resolution_clock::now();
+    auto elapsed = chrono::duration_cast<std::chrono::nanoseconds>(end - begin);
+    cout << "EXECUTED IN: " << elapsed.count() * (1e-6) << " ms" << endl;
+
+    cout << "\n";
+}
+
+int main(int argc, char* argv[]) {
+    GrowingAnnuity a;
+    a.fixed_amount = atof(argv[FIXED_AMOUNT]);
+    a.fixed_interest_rate = atof(argv[FIXED_INTEREST_RATE]);
+    a.fixed_interest_rate /= PERCENTILE;
+    a.fixed_growth_rate = atof(argv[FIXED_GROWTH_RATE]);
+    a.fixed_growth_rate /= PERCENTILE;
+    a.fixed_time = atoi(argv[FIXED_TIME]);
+
+    printGrowingAnnuityDetails(a);
+
+    closedFormGrowingAnnuity(a);
+
+    loopFormGrowingAnnuity(a);
+
+    cout << "We have reached the end..." << endl;
+}