If variable is not initialized in main function

[Jaisudha]

I have read in lots of books that you should initialize every variable declared the program. I don't know what is the theory behind this. Can you let me know what happens when a variable is not initialized in the function.

Can anyone explain me why this is with suitable example? so that is will be easy to understand for me

[Zecho]

See the below program, in which I have not initialized the value of variable 'r'.Please try to run this program and see what's happen

main()
{
int r;
printf(“%d”,r);
p= sample()
}

sample()
{
printf(“Testing program”);
}

Output of above code:

r=256

Here I got output 256 for 'r', you may get another value because i have not initialized the value for 'r'. So When you will run this code you will get any garbage value.

[Reegan]

If a variable is not declared in the main function of program, you are not able to use the variable in the program unless it is already defined as a global variable.

Initialization process is required to assign value to the declared variable.
if you do not initialize ,it will store a garbage value it.(Garbage value is the any value generated by computer itself)

[opaper]

Hi ,

It is very important to initialize each every variable in the program otherwise it will give you unexpected output.
Please also note that initializing a variable is only done exactly once when the computer loads your program into memory for execution. Which means all initializations are done only before the program starts it's execution.

I hope this information will definitely resolve your queries regarding variable initialization.