Q1. FIND SUM OF 5 NATURAL NUMBERS

Q2. FIND THE AREA OF CIRCLE

Q3. CALCULATE THE SIMPLE INTEREST

Q4. SWAP TWO NUMBERS

Q5. FIND THE LARGEST NUMBER

Q6. CHECK IF THE YEAR IS A LEAP YEAR OR NOT

Q7. MAKE A CALCULATOR USING SWITCH CASE

Q8.INPUT STUDENT RESULT MARKS AND CATEGORIZE

WHETHER IN FAIL, 1ST DIVISION

OR 2ND DIVISION

Q9. FIND FACTORIAL OF A NUMBER

Q10. FIND FIBONACCI SERIES

Q11. FIND REVERSE OF A NUMBER

Q12. ENTER A FIVE DIGIT NUMBER AND CALCULATE THE SUM OF ITS DIGITS

Q13. CHECK IF NUMBER IS A PRIME NO

Arithmatic Operators

#!/bin/sh

a=10
b=20
val=`expr $a + $b`
echo "a + b : $val"

val=`expr $a - $b`
echo "a - b : $val"

val=`expr $a \* $b`
echo "a * b : $val"

val=`expr $b / $a`
echo "b / a : $val"

val=`expr $b % $a`
echo "b % a : $val"

if [ $a == $b ]
then
   echo "a is equal to b"
fi

if [ $a != $b ]
then
   echo "a is not equal to b"
fi

a + b : 30
a - b : -10
a * b : 200
b / a : 2
b % a : 0
a is not equal to b

Follow the simple steps below:

192.168.1.88 for me. 
10.0.2.26 for Amity Labs.

OR vi prog_name.sh

Backspace doesn't work, use DEL which deletes backwards.

One (Insert Mode)
receives keyboard input as it is to type in and complete the program.

Left & Right arrow keys work fine, but the up and down arrow keys leave an unwanted character behind. 

The other(Command Mode),
is basically another command line to make edits on inputted lines, like

delete line: d + d (double click d)
delete character: d + (space) 
...

STARTING vi

   
     vi filename             edit a file named "filename"

     vi newfile              create a new file named "newfile"

ENTERING THE INSERT MODE

i               Begin inserting text at current cursor location 

        a		Begin appending text, one character to the right of current
	        	cursor location

I		Begin inserting text at the beginning of the current line

A		Begin appending text at the end of the current line

R              Begins replacing text from cursor location

o		Begin entering text one line below current line

O              Begin entering text one line above current line

ESC		Exit insertion mode and return to command mode

CLOSING AND SAVING A FILE

ZZ save file and exit VI

:wq		        same as above

:e!		        return to last saved version of current file

:q	        	quit without save, 

:q! is required if changes have been made

:w		        write without exit 

:w! to force write

MOVING AROUND IN A FILE

     h                    Move cursor left one space

     j                     Move cursor down one line

     k                    Move cursor up one line

     l                    Move cursor right one space

    <Arrow Keys>    These work too 

     w                   forward word by word

     b                    backward word by word

     e                    move forward to the end of current word

     $                    to end of line

     0 (zero)           to beginning of line

     H                    to top line of screen

     M                    to middle line of screen

     L                     to last line of screen

     G                     to last line of file

     nG                   to nth line of file

1G        to first line of file

     <Control> + f        scroll forward one screen

     <Control> + b       scroll backward one screen

     <Control> + d       scroll down one-half screen

     <Control> + u       scroll up one-half screen

NOTEPAD COMMANDS:

(Copy & Delete/Cut & Paste)            

x 		    delete/cut one character (destructive backspace)
d + (space)     Same as above

dw		    delete/cut the current word 
                         ndw deletes following (n-1) wprds including current (1)

dd 		    delete/cut the current line
                         ndd deletes following (n-1) lines incl current (1)

D		    delete/cut all content to the right of the cursor
d$		    same as above

y + (space)    Copy current character

yy                Copy or "yank" the current line
                         nyy copies following (n-1) lines incl current (1)

p		    paste what was cut last
p/P		    pasting a line below/above current line

c + (space)     deletes current character and opens insert mode at spot
                    (basically CHANGE COMMAND)
r                   same as above but known as REPLACE
s                   same as above but known as SUBSTITUTE
C                  deletes all from cursor to end of line, enters insert mode

S                  deletes the WHOLE line, then enters insert mode.

R                   All input from cursor point replaces previous text

J                   Joins next line with the current line (removes newline)
                            nJ joins following n-1 lines to current line (1)

(Undo & Redo)     

u		    undo last (command mode) edit

.		                  redo last

(Search)

/string search forward for occurrence of string in text

?string search backward for occurrence of string in text

n          move to next occurrence of search string

N          move to next occurrence of search string in opposite direction

(Line Number)

:.=	        returns line number of current line at bottom of screen

:=	        returns the total number of lines at bottom of screen
nG             move to nth line of file

(Quickie)

Command                                 Text Object

d (delete)	                        w (word to the left)
y (yank/copy)                	b (word to the right or backward)
c (change)	                        e (end of word)
                                        <space> (current character)
		                        H (top of the screen)
		                        L (bottom of the screen)
		                        M (middle of the screen)

		                        0 (zero - first character on a line)
		                        $ (end of a line)

		                        ( (previous sentence)
		                        ) (next sentence)
		                        [ (previous section)
		                        ] (next section)