Doubt about how to fill two-dimensional array in Java

Question

I’m doing an exercise and I need help. That’s the statement:

Calculate average temperatures for each month. For this, create a list containing the names of each month in the rows, and the number of days of each month in the columns. On each day, store each temperature value written by the user. Then, average the temperatures of each month.

Here follows the code I’ve already made, but I don’t even know how to do it right since I’m a beginner in Java:

import java.util.Scanner;

public class MediaTemperaturas {

public static void main (String args[]) {

double mês = new double[12][31];

for (int i = 0; i<11; i++);

Scanner sc = new Scanner (System.in);

String nomesMeses = sc.nextLine();

for (int j = 0; j<30;j++);

To not get too big this test, you can do it with smaller numbers, for example, 3 months, and each month contains 10 days (then you have to write 30 values (3 * 10), to get the result of the months). Can do:

double mes = new double [3][10];

**//Pra calcular a média, faz um:**

 int soma = 0;

 int media = 0;

 if (int i = 0; i < dias.length; i++) {



   soma += dias;

   media = soma/dias.length;

   return media;

}

My doubts:

• And how you get to write the name of every month on the line?

• How to fill in the values in each column?

Please, can someone help me make this algorithm?

Ah, there’s one more restriction: I can’t use the get, the set, the throw and the this, because what I am doing is very basic and of level well beginner.

Answer 1

Come on. First:

String[] meses = {
    "Janeiro", "Fevereiro", "Março", "Abril",  "Maio", "Junho",
    "Julho", "Agosto", "Setembro", "Outubro", "Novembro", "Dezembro"
};

// Vamos dizer que fevereiro tem 29 dias porque este ano é bissexto.
int[] diasNoMes = {31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};

Second, you can go through the days as follows:

for (int i = 0; i < meses.length; i++) {
    String nomeMes = meses[i];
    for (int j = 1; j <= diasNoMes[i]; j++) {
        System.out.print("Digite a temperatura do dia " + j + " de " + nomeMes + ":");
        temperaturas[i][j - 1] = sc.nextDouble();
    }
}

That j - 1 instead of just j is because the days start at 1, but the array starts at 0.

And if your temperatures are double, then its soma also has to be double and the media also has to be double.

I hope it helps you and you can develop your algorithm.