Programming In C++

1. Programming In C++ Spring Semester 2013 Lecture 3 Programming In C++, Lecture 3 By UmerRana

2. What is counter? What is repeat? What is decisions? Programming In C++, Lecture 3 By UmerRana

3. Assignment Operators Assignment operators abbreviate assignment expressions += -= *= /= %= Examples : If a=10 a += 1 or (a = a + 1) output is 11 a -= 1 or (a = a - 1) output is 9 a *= 1 or (a = a * 1) output is 10 a /= 1 or (a = a / 1) output is 10 a %= 1 or (a = a % 1) output is 0 Programming In C++, Lecture 3 By UmerRana

4. Increment / Decrement Operators Increment operator (++) Can be used instead of a+=1 or a=a+1 Decrement operator (--) Can be used instead of a-=1 or a=a-1 Example: If a equals 10, then printf( "%d", ++c ); Output 11 printf( "%d", c++ ); Output 10 In either case, c now has the value of 10 Programming In C++, Lecture 3 By UmerRana

5. Decision Making Equality operators == != Relational operators < > <= >= Programming In C++, Lecture 3 By UmerRana

6. Data Flow Diagram (DFD) Expression Show Flow Decision Process Programming In C++, Lecture 3 By UmerRana

7. Loops To execute a set of instructions repeatedly until a particular condition is being satisfied. Three types of looping statements are there 1)      For Loop 2)      While Loop 3)      Do while Loop Programming In C++, Lecture 3 By UmerRana

8. Loops Requires • The name of a counter variable • The initial value of the counter variable • A condition that tests for the final value of the counter variable (i.e., whether looping should continue) • An increment or decrement by which the counter variable is modified each time through the loop run Programming In C++, Lecture 3 By UmerRana

9. Loops For Loop For loop in C is the most general looping construct. In for looping statement allows a number of lines represent until the condition is satisfied. Syntax of for loop expression: For Loop expression is divided by semicolons into three separate expressions: the “Initialize expression”, the “test expression”, and the “Increment/Decrement expresssion” for(Initialize counter variable ;Condition;Increment/Decrement the counter variable) { Body of the for loop } Programming In C++, Lecture 3 By UmerRana

10. Initialization expression For Loop DFD Test Expression /Condition Exit False True Body of loop Increment / Decrement Expression Programming In C++, Lecture 3 By UmerRana

11. Loops Example: Print number 1 to 10 this way: 1 2 3 4 5 6 7 8 9 10 void main() { printf (“1\n”); printf(“2\n”); printf(“3\n”); printf(“4\n”); printf(“5\n”); printf(“6\n”); printf(“7\n”); printf(“8\n”); printf(“9\n”); printf (“10\n”); } Programming In C++, Lecture 3 By UmerRana

12. Loops Example: #include <stdio.h> void main() { int counter; for(counter = 1; counter <= 10; counter++ ) printf( "%d\n", counter ); } OutPut 1 2 3 4 5 6 7 8 9 10 Programming In C++, Lecture 3 By UmerRana

13. Loops OutPut Counter = 1 Total = 1 Counter = 2 Total = 2 Counter = 3 Total = 3 Counter = 4 Total = 4 Counter = 5 Total = 5 Counter = 6 Total = 6 Counter = 7 Total = 7 Counter = 8 Total = 8 Counter = 9 Total = 9 Counter = 10 Total = 10 Example of Multiple Statement: #include <stdio.h> void main() { int counter, total=0; for(counter = 1; counter <= 10; counter++ ) { total=total + 1; printf( “counter=%d, total=%d\n", counter,total); } } Programming In C++, Lecture 3 By UmerRana

14. Loops While Loop While loop in C is the other mostgeneral looping construct. The  while loop statement executes as long as a specified condition is true. Syntax of while loop expression: while ( condition ) { Code to execute, while the condition is true. } while(condition) { statement(s); } Programming In C++, Lecture 3 By UmerRana

15. Loops While Loop DFD Programming In C++, Lecture 3 By UmerRana

16. Loops Example • #include <stdio.h> • void main () • { • // Local variable declaration: • int a = 10; • // while loop execution • while( a < 20 ) • { • printf(“value of a is %d”,a); • a++; • } • } Programming In C++, Lecture 3 By UmerRana

17. Loops Example • #include <stdio.h> • void main () • { • // Local variable declaration: • int a = 0; • char ch=‘a’; • // while loop execution while (ch != ‘\r’) { printf(“Enter a character: \n”); ch=getche(); printf(“Entered Character is %c\n”,ch); } • } Programming In C++, Lecture 3 By UmerRana

18. Loops do while Loop • do… While loop is checks its condition at the bottom of the loop. • A do...while loop is similar to a while loop, except that a do...while loop is execute at least one time Syntax of do..while loop expression: do { statement(s); } while( condition ); Programming In C++, Lecture 3 By UmerRana

19. Loops do while Loop Programming In C++, Lecture 3 By UmerRana

20. Loops Example • #include <stdio.h> • void main () • { • // Local variable declaration: • int a = 10; • // while loop execution • do • { • printf(“value of a is %d”,a); • a++; • } while( a < 20 ) ; • } Programming In C++, Lecture 3 By UmerRana

21. Loops Nested Loop • One loop inside another loop . • In nested loop the inner loop is executed first and then outer. Syntax of for Nested Loop: for ( init; condition; increment ) { for ( init; condition; increment ) { statement(s); } statement(s); } Programming In C++, Lecture 3 By UmerRana

22. Loops Syntax of while Nested Loop: while(condition) { while(condition) { statement(s); } statement(s); } Programming In C++, Lecture 3 By UmerRana

23. Loops Syntax of do..while Nested Loop: do { statement(s); do { statement(s); } while( condition ); }while( condition ); Programming In C++, Lecture 3 By UmerRana

24. Loops Loop Control Statements: Loop control statements change execution from its normal sequence. When execution leaves a scope, all automatic objects that were created in that scope are destroyed Programming In C++, Lecture 3 By UmerRana

25. Loops Break Statements: • When the break statement is encountered inside a loop, the loop is immediately terminated and program control resumes at the next statement following the loop. • If you are using nested loops ( ie. one loop inside another loop), the break statement will stop the execution of the innermost loop and start executing the next line of code after the block true false Programming In C++, Lecture 3 By UmerRana

26. Loops Break Statements: #include <stdio.h> Void main () { /* local variable definition */ int a = 10; /* while loop execution */ while( a < 20 ) { printf("value of a: %d\n", a); a++; if( a > 15) { /* terminate the loop using break statement */ break; } } } Programming In C++, Lecture 3 By UmerRana

27. Loops Continue Statements: • continue forces the next repetition of the loop to take place, skipping any code in between. true false Programming In C++, Lecture 3 By UmerRana

28. Loops Continue Statements: #include <stdio.h> Void main () { /* local variable definition */ int a = 10; /* while loop execution */ while( a < 20 ) { printf("value of a: %d\n", a); a++; if( a == 15) { a++; continue; } } } Programming In C++, Lecture 3 By UmerRana

29. Loops Goto Statements: A goto statement provides an unconditional jump from the goto to a labeled statement in the same function. Syntex gotolabel .. . label: statement; true false Programming In C++, Lecture 3 By UmerRana

30. Loops Goto Statements: #include <stdio.h> void main () { /* local variable definition */ inta = 10; /* do loop execution */ LOOP:do { if( a == 15) { /* skip the iteration */ a ++; gotoLOOP; } printf("value of a: %d\n", a); a++; }while( a < 20 ); } Programming In C++, Lecture 3 By UmerRana

31. Quiz • How many type of loops we have? • What is the expression of the for loop? • What is the expression of the while loop? • What is the expression of the do.. while loop? • What is nested loop? • What break statement does? • What continue statement does? • What goto statement does? • What you have to do? Programming In C++, Lecture 3 By UmerRana

32. Assignment # 1 Q1. Differentiate between IDE and Command-Line Development System. Explain the program execution process and environment with the help of diagram? Q2. Explain the following terms with appropriate examples: • Getche() • Printf() • Scanf() Programming In C++, Lecture 3 By UmerRana