Control statements and functions in c
- 1. Control Statements and Functions in C V.V.Subrahmanyam, Sr. Lecturer, SOCIS, IGNOU Date: 04-02-07 Time: 1-00 to 1-45
- 2. Control Statements Branching: The if statement If – Else statement Looping: While Statement Do-while statement For Statement Switch statement
- 3. If statement If (expr) statement Example: if (x<0) printf (“ %d”, x);
- 4. If – else statement If (expr) statement1; else statement2; Example: if (status == ‘s”) tax = 0.20 * pay; else tax = 0.14 * pay;
- 5. Nested if - else if e1 if e2 s1 else s2 else if e3 s3 else s4
- 6. While statement while (expr) { statement(s); } Example: int digit=9; while(digit <= 9) { printf(“%dn”, digit); ++digit; }
- 7. Do – while statement Do statement while (expr); Example: { int digit = 10; do printf(“%dn”, digit); while (digit <= 9); }
- 8. For loop For (expr1; expr2; expr3) statement Example: int I; for (i=0;i<=10; i++) { printf(“%d”, i); }
- 9. Break statement It can be used within a for, while , do- while, or a switch statement. It is used to terminate a loop or to exit from a switch statement in a convenient way when a condition is met, if any error or irregular condition is detected.
- 10. Continue statement It is used to bypass the remainder of the current pass through a loop. The loop does not terminate when a continue statements is encountered. Rather, the remaining loop statements are skipped and the computation proceeds directly to the next pass through the loop.
- 11. Goto statement The goto statement is used to alter the normal sequence of program execution by transferring control to some other part of the program. goto label; --- --- Label: statement;
- 12. Functions The use of user-defined functions allows a large program to be broken down into a number of smaller, self- contained components, each of which has some unique, identifiable purpose. The C program can be modularized through the intelligent use of such functions. Avoids the need of repeated programming of the same instructions.
- 13. Types of functions Functions with no parameters and no return value Functions with parameters and no return value Functions with parameters and with return value.
- 14. Function Declaration Prototype declaration at the declaration part. Data-type fname(type1 arg1, type2 arg2);
- 15. Function definition Actual statements of the function to solve the specified task.