Vamsi Pavan’s Place

Linked Lists
Given only a pointer to a node to be deleted in a singly linked list, how do you delete it?
Write a C program to implement a Generic Linked List.
How would you detect a loop in a linked list? Write a C program to detect a loop in a linked list.
How do you find the […]

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Bit wise operators and % operator cannot be applied to float
fmod() is to find modulus for float as % is for int
but it needs math.h;
This can be used to detect whether a given number is an integer or a float value;
fmod(Var,1.0)==0 ? printf(”Yes it is integer”) : printf(”Not an integer”);
Bit fields
Bit fields can be used […]

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#if something == 0
int some=0;
#endif
main(){
int thing = 0;
printf(”%d %d\n”, some ,thing);
}
Answer
0 0
Explanation
This code is to show that preprocessor expressions are not the same as the ordinary expressions. If a name is not known the preprocessor treats it to be equal to zero.

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main(){
int *j;
{
int i=10;
j=&i;
}
printf(”%d”,*j);
}
Answer:
10
The variable i is a block level variable and the visibility is inside that block only. But the lifetime of i is lifetime of the function so it lives upto the exit of main function. Since the i is still allocated space, *j prints the value stored in i since j points i.

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Unary + is the only dummy operator in C, you can just ignore this operator.
i = - -1

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When the compiler sees a new function (ex. show) about which it doesn’t know anything. It by default assumes the function to be returning int. But when compiler sees the actual definition of function (show), if mismatch occurs (might be because of other return type) error is generated.
main(){
show();
}
void show(){
printf(”I’m the greatest”);
}
The solutions are as follows:
1. […]

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labels (ex. goto ) have functions as scope. Labels which are outside the functions are not visible to this statement and cause compilation error.

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%p

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‘\n’

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!, > , < …
the expression i+++j is treated as (i++ + j)
i++ + ++i

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