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CONTROL STRUCTURES IN AN ALGORITHM

                  Control structure is defined as an order of execution of a statement in an algorithm. There are
                  three types of control structures: sequential, selection, and repetition. Let us explore them in
                  detail.
                  Sequential

                  This is the simplest form of control structure, where instructions are executed in a sequential
                  order, one after the other. For example, steps for calculating the percentage of any student:

                  1.  Input marks for English, Hindi, and Maths.
                  2.  Total the marks.
                  3.  Calculate the percentage.
                  4.  Display the percentage.

                  Let us write some algorithms based on sequential control structure.

                  Algorithm 3: Write an algorithm for adding two numbers and displaying the result.
                  Step 1:  Start
                  Step 2:  Input num1 and num2.
                  Step 3:  Calculate Sum = num1 + num2.

                  Step 4:  Display sum.
                  Step 5:  Stop

                  Algorithm 4: Write an algorithm to calculate the area of the circle and display it.
                  Step 1:  Start
                  Step 2:  Input radius.

                  Step 3:  Calculate area = 3.14 * radius * radius.
                  Step 4:  Display area.
                  Step 5:  Stop

                  Algorithm 5: Write an algorithm to input the temperature in Fahrenheit and convert it into
                  Celsius and display it.

                  Step 1:  Start
                  Step 2:  Input temp in Fahrenheit.
                  Step 3:  Convert temp to Celsius = (temp - 32) * 5 / 9.
                  Step 4:  Display Celsius.
                  Step 5:  Stop
                  Selection

                  This structure allows the algorithm to make a decision based on a condition. If the condition is
                  true, a certain block of instructions is executed.  If the condition is false, an alternative block of
                  instructions will be executed. For example, if we consider the above example where we have a
                  condition: Award to be given if the percentage is more than 90.
                  1.  Input marks for English, Hindi, and Maths.
                  2.  Total the marks.



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