deeksha gopaliya
TRANSCRIPT
Made By :-Made By :-Deeksha Deeksha GopaliyaGopaliya
1111thth Science Science
COMPUTERCOMPUTER PROJECTPROJECT
COMPUTERCOMPUTER PROJECTPROJECT
LOOPSLOOPS
FORFOR LOOPLOOPFORFOR LOOPLOOP DODO WHILEWHILELOOPLOOP
DODO WHILEWHILELOOPLOOPWHILEWHILE LOOPLOOPWHILEWHILE LOOPLOOP
PARTS OF A LOOP
1. Initialization Expression - Before entering in a loop , its control variables must be initialized. The initializations expression gives the loop variables their first value.
2. Test Expression - The test expression is the expression whose truth value decides whether the loop body will be executed or not.
3. Update Expression - The update expression change the values of loop variables. The update expression is executed ; at the end of the loop after loop body is executed.
4. The body of the Loop – The statements that are executed repeatedly as long as the condition is true ,form the body of loop.
FOR LOOPFOR LOOPFor Loop executes a sequence of
statements multiple timeand abbreviates the code that manages the
loop variable.Syntax: for (initialization; condition; update
expression) Body of the loop;Example: #include<iostream.h>
output: void main( ) 1 { 2 for (int i=0; i<=5; i++) 3 cout<<“\n”<<i; Body of loop 4 } 5
Functioning of For Loop in C++
For loop is used when we don’t know in advance how many times the loop will times the loop will be executed .
The loop terminates as soon as the condition becomes false.
EXIT
WHILEWHILE LOOPLOOPWhile loop While loop is an entry-controlled loop. It repeats a
statement or group of statements while a condition is true. It tests the condition before executing the loop.
Syntax: initialization; while (condition) loop=body; updating expression;
Example : #include<iostream.h> Output:
void main( ) 1
{ 2
int i=1 Initialization expression 3 while (i<=5)
4 cout<<“\n”<<i; Body of loop 5 i++; Update expression }
DO WHILE LOOPDO WHILE LOOPDo while LoopDo while Loop is a exit-controlled loop. It evaluates its text
expression at the bottom of the loop after executing the loop body statements.
Syntax: initialization; do { loop body; updating expression; }while (condition); Example: #include<iostream.h. Output: void main( ) 1 {int i=1 Initialization expression 2 do 3 { 4 cout<<“\n”<<i; Body of loop 5 i++; Update expression 6 }while (i<=5) }
Comparison between while loop and do while loop
While loop test condition before executing the loop body whereas do while loop test condition after executing loop body.
While loop is a entry-controlled loop whereas do while loop is a exit-controlled loop.
While loop is preferred when we don’t want to execute the loop body even once in case the condition is false whereas do while loop is preferred when we want to execute the loop body at least once.
Functioning of Nested Loop
Example:#include<iostream.h>void main( ){for( int i=1; i<=3; i++){for( int j=1; j<=i; j++) {cout<<i;}cout<<“\n”;} }
Inner
Loop
Outer
Loop
Output:11
1212
123123