Go4Expert - How this Actually Works

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How this Actually Works

int a=10,b;
b=a++ + ++a;

specially with a++ ?

Re: 100 Multiple choice questions in C

int a=10,b;
b=a++ + ++a;
how this actually works ?

Re: How this Actually Works

Whatever result you see is undefined because you are using modifiers more than once on the same variable in the same statement.

Re: How this Actually Works

For prefix increment:

Code:

int a=10;

printf( "%d" , ++a);

The output will be 11. I am sure you understand it why?

For postfix increment:

Code:

int a=10;

printf( "%d" , a++);

The output will be 10. It is because, the value of a is returned first then only it is increased by 1.

Here is another example:

Code:

int a=10, b;

printf( "%d" , a++);    // 10 is displayed

++a;                   // a becomes 12 after this statement

In you example, it doesn't matter if you use prefix or postfix increment but there are cases when, prefix and postfix increment gives different result.