# Category Archives: GFacts

## GFact 23 | (Brocard’s problem)

Brocard’s problem is to find values of m and n such that n!+1 = m2 For example, a pair (4, 5) solves the above equation.… Read More »

## GFact 22 | (2^x + 1 and Prime)

A number of the form 2x + 1 (where x > 0) is prime if and only if x is a power of 2, i.e.,… Read More »

## G-Fact 21 | Collatz Sequence

Starting with any positive integer N, we define the Collatz sequence corresponding to N as the numbers formed by the following operations: N → N/2… Read More »

## G-Fact 20 (Cayley’s formula for Number of Labelled Trees)

Consider below questions. How many spanning trees can be there in a complete graph with n vertices? How many labelled Trees (please note trees, not… Read More »

## G-Fact 19 (Logical and Bitwise Not Operators on Boolean)

Most of the languages including C, C++, Java and Python provide the boolean type that can be either set to False or True. Consider below… Read More »

## G-Fact 18 | Finding nth Fibonacci Number using Golden Ratio

We have discussed different methods to find nth Fibonacci Number.

## G-Fact 17

Storage class of a variable determines whether the item has a global or local lifetime. In C, typedef is considered as a storage class like… Read More »

## fseek() vs rewind() in C

In C, fseek() should be preferred over rewind().

## G-Fact 16

Predict the output of following program.

## G-Fact 15

Atomic Operation What is an atomic operation? An idea of atomic operation helps in understanding reentrancy, critical section, thread safety, synchronization primitives, etc… (we will… Read More »

## G-Fact 14

In C, a structure cannot have static members, but in C++ a structure can have static members.

## G-Fact 13

const Behaviour in C and C++ In C, the const qualified identifiers will have external linkage, where as in C++ it will have internal linkage.… Read More »

## G-Fact 12

In C, struct keyword must be used for declaring structure variables, but it is optional in C++.

## G-Fact 11

Following relationship holds in any n-ary tree in which every node has either 0 or n children. L = (n-1)*I + 1

## G-Fact 10

Enumeration constants (enum values) are always of type int in C, whereas they are distinct types in C++ and may have size different from that… Read More »