using System;

public class Program

{

    public static void Main()

    {

 Console.WriteLine("This program will analize the statistics of Covid 19 and in addition");

            Console.WriteLine("to seeing the forecast of infected, deaths and recovered by Covid 19 in Mexico and China.");

            Console.WriteLine("\nPlease Enter the number of day to forecast");

​

            //This will be our variable to compare and forecast the situation in China and Mexico

            double X;

            X = double.Parse(Console.ReadLine());

​

            //We are going to declare all the variables we are going to use

            double E1nyx = 0;

            double E1ny = 0;

            double Ex = 0;

            double Ex2 = 0;

            double Px = 0;

            double P1ny = 0;

            double a = 0;

            double b = 0;

​

            //Sample Size

            int sample = 10;

            //Variable "x" 

            double[] x = new double[10] { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };

            //Variable "y" this will replace in the formulas we ara going to use

            double[] y = new double[10] { 102762, 28, 48, 29, 41, 41, 21, 33, 31, 32 };

​

            //Create the cycle for

            for (int i = 0; i < sample; i++)

            {

                //First we add

                E1ny = E1ny + Math.Log(y[i]);

                E1nyx = E1nyx + Math.Log(y[i]) * x[i];

                Ex = Ex + x[i];

                Ex2 = Ex2 + x[i] * x[i];

            }

                //Then We multiply

            P1ny = E1ny / sample;

            Px = Ex / sample;

            b = ((sample * E1nyx) - (Ex * E1ny)) / ((sample * Ex2) - (Ex * Ex));

            a = Math.Exp(P1ny - (b * Px));

​

            Console.WriteLine("\n ---The exponential trend equation for Coronavirus infections in China--- ");

​

            Console.WriteLine("The equation used to forecast the number of people infected in China by COVID 19 is: ");

​

            //We define de equation

            Console.WriteLine("y= " + a + "e^(" + b + "x");

​

            //Variables to sustitute in the equation

            double fx;

            double h;

​

            fx = a * Math.Pow(Math.E, (b * X));

            h = Math.Round(fx);

​

            //It shows the forecast resault of infected people in China for COVID 19

            Console.WriteLine("The prognosis of those infected is: " + h + " people infected in China in April 2021 in " + X + "  days ");

​

            //In Mexico we are going to analize from the 1st day of 2021 to the 10th day of the year, this ones are localizated in the variable "X"

            //The number of people its going to be "y" 

            Console.WriteLine("\n ---The exponential trend equation for Coronavirus infections in Mexico--- ");

​

            //We are going to use the same procedure to calculate but with the variables here in mexico since 1st 2021 to 10th 2021

​

            double MS1nyx = 0;

            double MS1ny = 0;

            double MSx = 0;

            double Msx2 = 0;

            double MPx = 0;

            double MP1ny = 0;

            double Ma = 0;

            double Mb = 0;

​

            int sampleMx = 10;

            //Samples from 1st January 2021 to 10th January 2021

            double[] Mx = new double[10] { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };

            double[] My = new double[10] { 11091, 6359, 5211, 6464, 11271, 13345, 13734, 14362, 16105, 10003 };

​

            for (int i = 0; i < sampleMx; i++)

            {

                MS1ny = MS1ny + Math.Log(My[i]);

                MS1nyx = MS1nyx + Math.Log(My[i]) * Mx[i];

                MSx = MSx + Mx[i];

                Msx2 = Msx2 + Mx[i] * Mx[i];

            }

​

            MP1ny = MS1ny / sampleMx;

            MPx = MSx / sampleMx;

            Mb = ((sampleMx * MS1nyx) - (MSx * MS1ny)) / ((sampleMx * Msx2) - (MSx * MSx));

            Ma = Math.Exp(MP1ny - (Mb * MPx));

            //We show the equation we are going to use 

            Console.WriteLine("The equation used to forecast the number of people infected in Mexico by COVID 19  is: ");

            Console.WriteLine("y=" + Ma + "e^(" + Mb + "x");

​

            double Mfx;

            double Mh;

​

            Mfx = Ma * Math.Pow(Math.E, (Mb * X));

            Mh = Math.Round(Mfx);

            Console.WriteLine("The prognosis of those infected is: " + Mh + " people infected in Mexico in 2021 in " + X + " days");

​

​

            Console.WriteLine("\n ---The Exponential Trend Equation of Predicted Coronavirus Deaths in China--- ");

​

            double CD1nyx = 0;

            double CD1ny = 0;

            double Csx = 0;

            double Csx2 = 0;

            double CPx = 0;

            double CP1ny = 0;

            double Ca = 0;

            double Cb = 0;

​

            int sampleCn = 10;

            //2021 January Death toll China 

            double[] Cx = new double[10] { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };

            double[] Cy = new double[10] { 1, 2, 2, 2, 2, 2, 1, 1, 2, 2 };

​

            for (int i = 0; i < sampleCn; i++)

            {

                CD1ny = CD1ny + Math.Log(Cy[i]);

                CD1nyx = CD1nyx + Math.Log(Cy[i] * Cx[i]);

                Csx = Csx + Cx[i];

                Csx2 = Csx2 + Cx[i] * Cx[i];

            }

​

            CP1ny = CD1ny / sampleCn;

            CPx = Csx / sampleCn;

            CPx = Csx / sampleCn;

            Cb = ((sampleCn * CD1nyx) - (Csx * CD1ny)) / ((sampleCn * Csx2) - (Csx * Csx));

            Ca = Math.Exp(CP1ny - (Cb * CPx));

            //We show the equation we are going to use 

            Console.WriteLine("The exponential equation for forecasting deaths predicted by Coronavirus in China is: ");

            Console.WriteLine("y=" + Ca + "e^(" + Cb + "x)");

​

            double Cfx;

            double Ch;

​

            Cfx = Ca * Math.Pow(Math.E, (Cb * X));

            Ch = Math.Round(Cfx);

​

            Console.WriteLine("The forecast is: " + Ch + " people killed by Covid19 in China 2021 in " + X + " days");

​

            Console.WriteLine("\n---The exponential trend equation for deaths from Coronavirus in Mexico---");

​

            double MD1nyx = 0;

            double MD1ny = 0;

            double MDsx = 0;

            double Mdsx2 = 0;

            double MDPx = 0;

            double MDP1ny = 0;

            double Mda = 0;

            double Mdb = 0;

​

            int sampleMxD = 10;

​

            //January 2021 death toll in Mexico

            double[] MDx = new double[10] { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };

            double[] MDy = new double[10] { 661, 641, 644, 654, 666, 691, 704, 731, 798, 806 };

​

            for (int i = 0; i < sampleMxD; i++)

            {

                MD1ny = MD1ny + Math.Log(MDy[i]);

                MD1nyx = MD1nyx + Math.Log(MDy[i]) * MDx[i];

                MDsx = MDsx + MDx[i];

                Mdsx2 = Mdsx2 + MDx[i] * MDx[i];

            }

​

            MDP1ny = MD1ny / sampleMxD;

            MDPx = MDsx / sampleMxD;

            Mdb = ((sampleMxD * MD1nyx) - (MDsx * MD1ny)) / ((sampleMxD * Mdsx2) - (MDsx * MDsx));

            Mda = Math.Exp(MDP1ny - (Mdb * MDPx));

            //We show the equation we are going to use 

            Console.WriteLine("The exponential equation for forecasting deaths from Coronavirus in Mexico is:");

            Console.WriteLine("y=" + Mda + "e^(" + Mdb + "x)");

​

            double MDfx;

            double MDh;

​

            MDfx = Mda * Math.Pow(Math.E, (Mdb * X));

            MDh = Math.Round(MDfx);

​

            Console.WriteLine("The forecast is: " + MDh + " deaths from Covid19 in Mexico in 2021 in " + X + " days");

​

            Console.WriteLine("\n---The exponential trend equation of people vaccinated in China---");

​

            double CV1nyx = 0;

            double CV1ny = 0;

            double CVsx = 0;

            double CDsx2 = 0;

            double CVPx = 0;

            double CVP1ny = 0;

            double Cva = 0;

            double Cvb = 0;

​

            int sampleVacc = 10;

​

            //Vaccinated people, we will take as a sample from the first dose that was applied in China in April of 2021

            double[] CVx = new double[10] { 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 };

            double[] CVy = new double[10] { 133801000, 136677000, 139970000, 142802000, 145920000, 149071000, 155150000, 161121000, 164471000, 167343000 };

​

            for (int i = 0; i < sampleVacc; i++)

            {

                CV1ny = CV1ny + Math.Log(CVy[i]);

                CV1nyx = CV1nyx + Math.Log(CVy[i]) * CVx[i];

                CVsx = CVsx + CVx[i];

                CDsx2 = CDsx2 + CVx[i] * CVx[i];

​

            }

​

            CVP1ny = CV1ny / sampleVacc;

            CVPx = CVsx / sampleVacc;

            Cvb = ((sampleVacc * CV1nyx) - (CVsx * CV1ny)) / ((sampleVacc * CDsx2) - (CVsx * CVsx));

            Cva = Math.Exp(CVP1ny - (Cvb * CVPx));

            //We show the equation we are going to use 

            Console.WriteLine("The exponential equation for forecasting vaccines from Coronavirus in China is: ");

            Console.WriteLine("y=" + Cva + "e^(" + Cvb + "x)");

​

            double CVfx;

            double CVh;

​

            CVfx = Cva * Math.Pow(Math.E, (Cvb * X));

            CVh = Math.Round(CVfx);

​

            Console.WriteLine("The forecast is: " + CVh + " vaccines aplicated from Covid19 in China in 2021 in " + X + " days");

​

            Console.WriteLine("\n---The exponential trend equation of people vaccinated in Mexico---");

​

            double MV1nyx = 0;

            double MV1ny = 0;

            double MVsx = 0;

            double MDsx2 = 0;

            double MVPx = 0;

            double MVP1ny = 0;

            double Mva = 0;

            double Mvb = 0;

​

            int sampleVaccMX = 10;

​

            //Vaccinated people at leaste one dosis in Mexico since the begin in January 2021

            double[] MVx = new double[10] { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };

            double[] MVy = new double[10] { 2924, 6824, 9579, 18529, 24998, 43960, 48236, 53185, 58402, 67468 };

​

            for (int i=0; i<sampleVaccMX;i++)

            {

                MV1ny = MV1ny + Math.Log(MVy[i]);

                MV1nyx = MV1nyx + Math.Log(MVy[i]) * MVx[i];

                MVsx = MVsx + MVx[i];

                MDsx2 = MDsx2 + MVx[i] * MVx[i];

            }

            MVP1ny = MV1ny / sampleVaccMX;

            MVPx = MVsx / sampleVaccMX;

            Mvb = ((sampleVaccMX * MV1nyx) - (MVsx * MV1ny)) / ((sampleVaccMX * MDsx2) - (MVsx * MVsx));

            Mva = Math.Exp(MVP1ny - (Mvb * MVPx));

​

            Console.WriteLine("The exponential equation for forecasting vaccines from Coronavirus in Mexico is: ");

            Console.WriteLine("y=" + Mva + "e^(" + Mvb + "x)");

​

            double MVfx;

            double MVh;

​

            MVfx = Mva * Math.Pow(Math.E, (Mvb * X));

            MVh = Math.Round(MVfx);

​

            Console.WriteLine("The forecast is: " + MVh + " at least one vaccine aplicated from Covid19 in Mexico in 2021 in " + X + " days");

​

    }

}