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What is a Sequence?

            A sequence in programming is an ordered set of instructions or tasks. In case, if you follow the
            wrong order, then the task cannot be achieved, or you may get the unexpected results.
            Example of sequence is an algorithm, which is a detailed step-by-step process that needs to be
            followed in order to complete a task or to solve a problem.
            Benefits of using Sequences in coding:

            •  Our manner of thinking can be easily replicated in sequence programming.
            •  Sequence of programming reflects logical thinking.
            Example: Algorithm of your daily routine

            You daily routine is a series of actions which you do every day as follows.

             Step 1   Wake up                           Step 7   Get back home
             Step 2   Take a shower                     Step 8   Watch TV

             Step 3   Have breakfast                    Step 9   Do homework

             Step 4   Go to school                      Step 10   Play
             Step 5   Attend classes                    Step 11   Have dinner

             Step 6   Have lunch                        Step 12   Go to sleep

            The above routine may vary from person to person but for a specific person this might be the routine.
            An algorithm is a process or set of rules which need to be followed to solve the given problem.
            Example: Algorithm to calculate the sum of two numbers.

             Step 1   Input first number (Num1)         Step 3   Sum = Num1 + Num2

             Step 2   Input second number (Num2)        Step 4   Print Sum

            In the above example, if we swap Step 3 and Step 4, i.e. you are instructing computer to Print Sum
            first and after that add Num 1 and Num 2; the program will not give the required result or give an
            error. This is called a bug.

            Sequencing with Loops and Conditions

            While writing an algorithm,three basic building blocks are used, sequencing, selection and iteration.
            Building blocks help us to uncover the solution to a complex problem which can be understood and
            implemented by others using programming.
            To understand the concept of sequencing in programming.

            Let’s take an example of sequence:
            Example: Algorithm to swap two numbers.

             Step 1   READ num1, num2                   Step 4   num2 = temp

             Step 2   temp = num1                       Step 5   PRINT num1, num2

             Step 3   num1 = num2                       Step 6   Stop


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