Solving Learning Objectives After learning the concepts in this chapter, the students will be able • To know the notations used in algorithmic techniques. • To understand Composition and Decomposition in algorithmic techniques. Chapter Page - - programming language. However, even pseudo code must be rigorous and correct.
Pseudo code is the most widely used notation to represent algorithms. . . Flowcharts Flowchart is a diagrammatic notation for representing algorithms.
They show the control flow of algorithms using diagrams in a visual manner. In flowcharts, rectangular boxes represent simple statements, diamond-shaped boxes represent conditions, and arrows describe how the control flows during the execution of the algorithm. A flowchart is a collection of boxes containing statements and conditions which are connected by arrows showing the order in which the boxes are to be executed. .
A statement is contained in a rectangular box with a single outgoing arrow,which points to the box to be executed next. S . A condition is contained in a diamond- shaped box with two outgoing arrows, labeled true and false. The true arrow points to the box to be executed next if the condition is true, and the false arrow points to the box to be executed next if the condition is false.
C true false . Parallelogram boxes represent inputs given and outputs produced. Inputs Outputs . Special boxes marked Start and the End are used to indicate the start and the end of an execution: Start End The flowchart of an algorithm to compute the quotient and remainder after dividing an integer A by another integer B is shown in Figure .
, illustrating the different boxes such as input, output, condition, and assignment, and the control flow between the boxes. The algorithm is explained in Example . . Enter A,B q,r:=q+ ,r-B q,r:= ,A r > B true false r,q Exit Figure .
: Flowchart for integer division Flowcharts also have disadvantages. ( ) Flowcharts are less compact than representation of algorithms in programming language or pseudo code. ( ) They obscure the basic hierarchical structure of the algorithms. ( ) Alternative statements and loops are disciplined