Target Cell-limited - C++

#include <iostream>
#include "ode_def.h"
#include <cpgplot.h>
#include <cmath>

using namespace std;

double dTdt(double b, double Tt, double Vt) {
    return -b * Tt * Vt;
}

double dIdt(double b, double s, double Tt, double Vt, double It) {
    return b * Tt * Vt - s * It;
}

double dVdt(double p, double c, double Vt, double It) {
    return p * It - c * Vt;
}

int main() {
    
	    int n = 7000;

    	double tstart = 0, tend = 7, deltaT = 0.001;
	
	    //Parameters
    	double b = 3.4*pow(10,-4.54), s = 3.4, p = 7.9e-3, c = 3.3;

	    //Initial Values
    	double T0 = 4 * std::pow(10, 8), I0 = 0.0001, V0 = 0.35;

    	double t = tstart, Tt = T0, It = I0, Vt = V0;

    	float tp[n + 1];
    	float Tp[n + 1];
    	float Ip[n + 1];
    	float Vp[n + 1];

    	tp[0] = tstart;
    	Tp[0] = T0;
    	Ip[0] = I0;
    	Vp[0] = V0;

    	for (int i = 0; i <= n; i++) {
        	t += deltaT;
        	Tt += deltaT * dTdt(b, Tt, Vt);
        	It += deltaT * dIdt(b, s, Tt, Vt, It);
        	Vt += deltaT * dVdt(p, c, Vt, It);

        	tp[i + 1] = t;
        	Tp[i + 1] = Tt;
        	Ip[i + 1] = It;
        	Vp[i + 1] = Vt;
    	}

    	if (!cpgopen("/XWINDOW")) return 1;

    	cpgenv(tstart, tend, 1e-5, 4e8, 0, 0);

    	cpglab("Time (days)", "Population", "Influenza A Model");

    	//dTdt
    	cpgsci(13);  //Pink
    	cpgline(n + 1, tp, Tp);

    	//dIdt
    	cpgsci(2);  //Red
    	cpgline(n + 1, tp, Ip);

    	//dVdt
    	cpgsci(3);  //Green
    	cpgline(n + 1, tp, Vp);

    	cpgtext(tstart + 4, 3.5e8, "dT/dt (Pink)");
    	cpgtext(tstart + 4, 3e8, "dI/dt (Red)");
    	cpgtext(tstart + 4, 2.5e8, "dV/dt (Green)");

    	cpgend();

    	return 0;
}