You have to write a Java program calculating the sum following sum:

1-1/4+1/9-1/16+...

• start by creating a class Sum [you will need to create a file Sum.java for it]
• import ptolemy.plot*.
• in your main method:
  • create double variable sum, initialize it with 0
  • create a double variable ds, initialize it with 1 (this will be your sum term)
  • create a double variable i, initialize it with 1 (this will be your loop counter)
  • create two boolean variables b1, b2, initialize them with false
  • define Plot variable myPlot
  • start a do loop, in each iteration of do loop:
    • increase sum: sum=sum+ds;
    • change ds for next iteration: ds=ds/(abs(ds)*i*i);
    • add a point (i,sum) to the first (0) set of myPlot
    • add a point (i,ds) to the second (1) set of myPlot
    • if b1 is false and absolute value of ds is smaller than 10^-4, assign true to b1
    • if b1 is true and b2 is false, print (on screen) the current number of iterations, and sum value; also assign true to b2
    • increase i by 1
    • check whether the absolute value of ds is larger than 10^-5
  • exit loop when absolute value of ds becomes smaller than 10^-5
  • print the total number of iterations (on screen), add this output as a comment to your code
  • display myPlot, print it (on paper)
• submit: code (along with the output it prints), and the printed graph(s)

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