Write a program step by step

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Write a program step by step
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Step 1 Problem definition.

• Given the coordinate of two points in 2-D space,
  compute and print their straight distance

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Step 2 Specifying the input and output.

• Input coordinates of point one (i.e X1, Y1) and
  coordinates of point two (i.e X2, Y2)
• Output distance between the points.
• For each of the input and output data you need to
  declare variables in your program.

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Step3 Solving some instances of the problem on
paper.

• Suppose the coordinates of point one is (X16,
  Y11) and coordinates of point two is (X22,
  Y24).
• The formula to compute the straight distance
  between two points given their coordinates is
• Distance sqrt( (X1-X2)2 (Y1 Y2)2).
• In this example the distance will be
• Distance sqrt( (6-2)2 (1-4)2) sqrt(42
  32) sqrt(25) 5.

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Step4 Writing the algorithm on paper

• Declare the input variables X1, Y1, X2, Y2 and
  output variable distance .
• Assign some values to the input variable.
• Compute the distance using the following formula
  and assign the results in distance.
• Distance sqrt( (X1-X2)2 (Y1 Y2)2).
• Print the value of distance on the screen.

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Step 5 Write the problem on paper

• include ltstdio.hgt
• include ltmath.hgt
• int main(void)
• / declaring the input and output variables /
• double X1, X2, Y1, Y2
• double distance
• / assign some values to the input variables /
• X1 6
• Y1 1
• X2 2
• Y2 4
• /compute the distance /
• distance sqrt((X1 X2)(X1 X2) (Y1
  Y2)(Y1 Y2))
• /print the results /
• printf(The distance is f \n, distance)
• return 0

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Step 7 Type the program

• Use a text editor to type your program.
• If you are typing your program in Unix you can
  use emacs, vim and pico .
• pico is the simplest one.
• Type pico myprog.c to start.
• Type in your program and press ctrlo to save.
• To exit press ctrlx.
• If you want to make some changes to your program
  after you exit type pico myprog.c

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Step 8 compile your program.

• The next step is to compile your program.
• Compiling means translating your program from C
  language to machine language.
• You need to do this because the system only
  understands the machine language.
• Type g myprog.c o myprog to compile your
  program.
• g is a compiler for C .
• If your program has syntax errors the compiler
  will print the appropriate messages on the
  screen. In such cases go back to your program (by
  typing pico myprog.c) and fix the problem.
• If your program is compiled successfully, no
  error message will be printed and the machine
  code will be written in the file myprog (with no
  extension)

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Step 9 Test your program.

• To run your program type ./myprog in Unix prompt.
• Test your program for different input values and
  see if it will produce the correct output.