4. algorithm
1 like1,084 views
An algorithm is a precise set of unambiguous instructions that must be completed in a finite number of steps to solve a problem or reach a desired outcome. Key features of algorithms include being precise, unambiguous, terminating after a finite number of steps, avoiding infinite repetition of instructions, and obtaining the desired result upon termination. Examples provided calculate equality of two numbers, print the first 10 natural numbers, and find the sum of the first N natural numbers. Flow charts and pseudo code can be used to represent algorithms graphically or as informal high-level descriptions.
![Example
• To print the first 10 natural numbers.
oStep 1: Start
oStep 2: [initialization] set i=1, n=10
oStep 3: Repeat step while i<=n
oStep 4: print i
oStep 5: Stop](https://image.slidesharecdn.com/4-190418110607/85/4-algorithm-7-320.jpg)
![Example
• To find sum of N natural numbers.
oStep 1: Start
oStep 2: Input N
oStep 3: [initialization] set i=1, sum=0
oStep 4: Repeat step while i<=N
oStep 5: set sum= sum+ i
Set i=i+1
oStep 4: print sum
oStep 5: Stop](https://image.slidesharecdn.com/4-190418110607/85/4-algorithm-8-320.jpg)
4. algorithm
- 4. Features of an Algorithm • Must be Precise. • Must be Unambiguous. • Should be completed in finite number of steps. • No instruction must be repeated infinitely. • Each step must follow a specified order. • After termination, desired result must be obtained.
- 6. Example • Test the equality of two numbers. o Step 1: Start o Step 2: Input first number as A o Step 3: Input second number as B o Step 4: if A=B then print “Equal” else Print “Not Equal” o Step 5: Stop
- 7. Example • To print the first 10 natural numbers. oStep 1: Start oStep 2: [initialization] set i=1, n=10 oStep 3: Repeat step while i<=n oStep 4: print i oStep 5: Stop
- 8. Example • To find sum of N natural numbers. oStep 1: Start oStep 2: Input N oStep 3: [initialization] set i=1, sum=0 oStep 4: Repeat step while i<=N oStep 5: set sum= sum+ i Set i=i+1 oStep 4: print sum oStep 5: Stop
- 9. Other Examples 1. Algorithm to find largest of three numbers. 2. To find whether a number is even or odd. 3. To find average of first N natural numbers. 4. To interchange / swapping of two variables. Using/without using third variable. 5. To find area of a circle of radius r. 6. To find simple interest and compound interest for principal p, rate r and time t. 7. To find roots of a quadratic equation.
- 11. Flow Chart • Graphical representation of steps followed to solve a given problem. • Flow chart helps the viewers to visualize the logic of the solution of a problem. • In flow chart, each step is depicted by a symbol and is associated with a short description.
- 13. • Calculate the sum of first 10 natural numbers. start Set i=1 and Sum=0 Set sum=sum+i and i=i+1 Is i>10? Display Sum End No Yes
- 14. Pseudo Code • It is a compact informal high-level description of an algorithm that uses the structural conventions of programming language. • Pseudo codes are an outline of a program that can easily be converted into programming statements.
- 15. Keywords used while writing pseudo codes: 1. IF (age>=18) then display eligible to vote ELSE display not eligible END IF
- 16. 2. WHILE (i<10) print i increment i by 1 END WHILE 3. FOR each student in the class add 10 as bonus marks END FOR