Algorithm and problem solving
Computers are widely used to solve problems. Algorithm design is the key factor in the problem solving. There is no specific method of problem solving. However, a general approach to problem solving can be thought of which is discussed below:
2.3.1 Defining the Problem
Success in solving problems mainly depends on understanding and defining the problem well. This preliminary step of problem solving is called problem definition phase. It involves working out what is to be done and listing the required inputs and expected outputs.
2.3.2 Problem Solving Strategies
There are many problem solving strategies repeatedly used in various problems. We can adopt any of these strategies which may suit the problem and write an efficient algorithm. The three common strategies are:
Divide and conquer strategy - This is the most widely used strategy. According to this strategy, one has to split the original problem into smaller sub-problems which can then be solved without further splitting. Solving a smaller problem gives clarity in understanding the problem and solving the problem. This breaking down method is found in many applications particularly in sorting and searching algorithms.
Dynamic programming - This method is used when the problem needs to be solved using intermediate steps. This method follows the strategy that solutions to larger problems can be had by finding solutions to smaller problems. It is widely used for operation research problems.
Backtracking - One method of problem solving is back tracking in which we start from solution to solve the problem. When the starting point of a solution is not very clear, assume the results that will be obtained and methods are derived from the output.
Breaking the Problem into Sub Problems
For algorithmic problem solving, clearly define the outline of the problem. Take one problem and break it into sub-problems. These sub-problems should be in such a way that the solution to the problem is clear. The communication between sub tasks should be precisely defined while breaking the task. This is the way to do a broader outline of solution for the entire problem. The breaking up of tasks into smaller tasks should be done till the sub tasks can be written as program statements.
The best example for the above is the Banking System. The sub tasks in banking system may include transactions, loans, fixed deposits etc. Each sub task communicates with the other task if necessary.
Data Structure
The data structure is the pattern in which the data should be stored. This is one of the primary factors which define the efficiency of an algorithm. There are no rules stating that the data structure is to be defined in the initial stage or while implementing the algorithm. For some problems, it is possible to define the data structure while designing and for others, it is done during implementing the algorithm.
Effective problem solving depends mainly on the choice of data structure. A small change in data organization can have a significant change in the algorithm. For example, if files are used to store data that has to be in sorted order it leads to inefficient and difficult implementation. Instead if arrays or linked lists are used, the algorithm and implementation will be much more efficient.
The points to be taken care of while choosing a data structure are:
l Data structure should be easily searchable
l Data structure should be easily updated
l Commonly used data structures should be used
l Data structure that supports excessive storage (dynamic storage) if required, should
be taken.
Some of the important data structures are array, linked list, queue, stack and binary tree. However, these topics are beyond the discussion of this unit.
Loops and Termination of Loops
The next step is to write a computational block of sub tasks. Computational statements are input, output statements, iterative blocks (loops), arithmetic expressions and assignment statements.
To construct loops, one must take care of initial conditions, termination condition, and the number of times it has to be executed. To establish an initial condition for a loop, take the smallest sample of the problem, set its value and check the value with all possible conditions.
In the example of adding numbers up to a given input number, the least value of that will be 0. The smallest sample of this problem is sum of number till 0. Let initial condition be "i" and result be "Sum".
i = 0
Sum = 0
The above is the solution if number is 0.
If number is greater than 0 then is initially i=0 and incremented by 1.
Let us take number is 5
While i<=5
{
i = i+1
Sum = sum + i
}
The next step is to set termination condition for loop. There are many ways a termination condition can be set. The simplest termination condition is limiting the iteration to the number of times the process is required.
E.g
For(i =0;i<n;i++)
sum = sum + array_value(i);
The another way of terminating the loop is terminating when some condition becomes false
Eg.
i = 0;
While(i<n)
Sum = sum + array_Value (i);
i++;
For(i =0;i<=5;i++)
sum = sum + i;
Another way of terminating the loop is terminating when some condition becomes false
While(i<=5)
Sum = sum + i;
Theory and lecture notes of Building Models all along with the key concepts of building models, essence of model-building, homework help, assignment help, understanding macroeconomics. Tutorsglobe offers homework help, assignment help and tutor’s assistance on Building Models.
Oil well, Oil field and reservoir tutorial all along with the key concepts of Oil Reservoir, Traps, Structural Traps, Stratigraphic Traps, Estimating Reserves, Oil in Place, Formation Volume Factor, Reservoir Engineering
tutorsglobe.com laboratory diagnosis of diphtheria assignment help-homework help by online corynebacterium diphtheria tutors
www.tutorsglobe.com offers reactions of carboxylic acids homework help, reactions of carboxylic acids assignment help, online tutoring assistance, organic chemistry solutions by online qualified tutor's help.
As per the classification according to nature costs can be categorized into Direct and Indirect.
tutorsglobe.com nature of coordination compounds assignment help-homework help by online types of salts tutors
tutorsglobe.com somatic embryogenesis assignment help-homework help by online micropropagation tutors
www.tutorsglobe.com offers system specification review homework help, assignment help, case study, writing homework help, online tutoring assistance by computer science tutors.
Theory and lecture notes of Post machine simulates Turing machine all along with the key concepts of post machine simulates turing machine, Equivalence of TMs, PMs and Markov Algorithms. Tutorsglobe offers homework help, assignment help and tutor’s assistance on Post machine simulates Turing machine.
Cost reduction programme aims at improvement of human efforts at all levels of the organisation which help in reducing costs.
tutorsglobe.com meningitis assignment help-homework help by online co-ordination systems tutors
tutorsglobe.com management of marketable securities assignment help-homework help by online working capital management tutors
tutorsglobe.com reduction assignment help-homework help by online dark reactions tutors
Batch costing is employed in which units of a product are manufactured in batches and employed in the assembly of the finishing product.
get notable content and round the clock support with top-rated meteorology assignment help service and score a++!
1950300
Questions Asked
3689
Tutors
1483110
Questions Answered
Start Excelling in your courses, Ask an Expert and get answers for your homework and assignments!!