An exception is a problem that arises during the execution of a program. A C++ exception is a response to an exceptional circumstance that arises while a program is running, such as an attempt to divide by zero or infinite loop etc.
Exceptions provide a way to transfer control from one part of a program to another. C++ exception handling is built upon three keywords: try, catch, and throw.
- throw: A program throws an exception when a problem shows up. This is done using a throw keyword.
- catch: A proram catches an exception with an exception handler at the place in a program where you want to handle the problem. The catch keyword indicates the catching of an exception.
- try: A try block identifies a block of code for which particular exceptions will be activated. It's followed by one or more catch blocks.
Assuming a block will raise and exception, a method catches an exception using a combination of the try and catch keywords. A try/catch block is placed around the code that might generate an exception. Code within a try/catch block is referred to as protected code, and the syntax for using try/catch looks like the following:
ALGORITHM:
Step 1: Start the program.
Step 2: Declare the variables a,b,c.
Step 3: Read the values a,b,c,.
Step 4: Inside the try block check the condition.
a. if(a-b!=0) then calculate the value of d and display.
b. otherwise throw the exception.
Step 5: Catch the exception and display the appropriate message.
Step 6: Stop the program.
PROGRAM:
#include#includevoid main(){ int a,b,c; float d; clrscr(); cout<<"Enter the value of a:"; cin>>a; cout<<"Enter the value of b:"; cin>>b; cout<<"Enter the value of c:"; cin>>c; try { If ((a-b) != 0) { d=c/(a-b); cout<<"Result is:"< } else { throw(a-b); } } Catch (int i) { cout<<"Answer is infinite because a-b is:"< } getch();}
Output:
Enter the value for a: 20
Enter the value for b: 20
Enter the value for c: 40
Answer is infinite because a-b is: 0
