An algorithm is a set of ordered steps or procedures necessary to solve a particular problem. An algorithm must be unambiguous and clear starting and stopping point. It is the verbal form of a program and independent of programming language. Each step in an algorithm tells what task is to be performed.

**Example:** An algorithm to find the area of a rectangle.

Step 1: Start

Step 2: Declare variables length, breadth, and area.

Step 3: Accept the length of the rectangle.

Step 4: Accept the breadth of the rectangle.

Step 5: Multiply the length and breadth of the rectangle and assign it to a variable area.

Step 6: Display the area of a rectangle.

Step 7: Stop.

### Guideline for an algorithm development

- Use Plain Language.
- Don’t use any programming language specific syntax because same algorithm can be implemented using any programming language.
- Every job to be done should be described clearly without any assumptions.
- It must have single entry and exit point.

### An excellent algorithm should have the following properties

**Finiteness –**Should have finite number of steps to solve the problem.**Definite –**Action of each step should be defined clearly without any ambiguity.**Inputs –**Input should be defined precisely.**Outputs –**Each algorith should result in one or more outputs.**Effectiveness –**It should be more effective among the different ways of solving the problem.

#### Q. Write an algorithm to find the sum of natural numbers up to the number entered by the user.

**Solution :**

**Step 1**: Start

**Step 2**: Declare variables number, i, sum.

**Step 3**: Initialize variable i = 1 and sum = 0.

**Step 4**: Read the positive number from the user.

**Step 5**: Repeat step 5 until i <= number.

. **Step 5.1**: sum = sum + i

. **Step 5.2**: i = i+1

**Step 6**: Display sum.

**Step 7**: Stop.