Looping In Text File

[Code] I want to replace the X and Y column to user enter value. For example If User enter X=100 Y=100. So the text File Should Do changes Like this:

In first line The X and Y should Be replace by 100. For the second line to the 10th line The X should X=X+2.54 and Y remain 100. For 11th line X=100 and Y=Y+2.54. From line 12 to 20 X=X+2.54 and Y remain which is 102.54. The pattern should be continue until end of file. For every 10 line the Y value should change. This Is the code to replace X and Y value: [Code]

code working perfectly for X values. But for Y values for the first 10 lines is no problem but after that the initial Y value is adding by 2.54 and that value should remain for 10 lines only but not for 20 lines.. Actually the number of lines is determined by the user. they need to enter the number of lines. User must decide to how many lines once the changes should take place.

And One more question is : If user enter Row= 2 the changes should occur for two set of lines only. If user enter Row =2 and column=10 So only 20 lines should changes other lines should remain the original value. I attach my text file after the replacement. But the replacement is still wrong.