q.c

#include <stdio.h>
#include <stdlib.h>

int main() {
	// your code goes here
	char *s1, *s2;
	printf("%d%d", sizeof(s1), sizeof(s2));
	return 0;
}

// codechef IDE gives answer - 4,4
// my machine gives - 8,8
// correct answer - 4,2

q1.9.c

# include <stdio.h>
# include <stdlib.h>


int main()
{
	extern int i;
    printf("\n%d",i);
     return 0;
 }
int i=20;

// how come this works?

q2-1.c

# include <stdio.h>

int main()
{

	int i=4;

	switch(i)
	{

		default:
			printf("\ndefault\n");

		case 1:
			printf("\ncase 1\n");
			break;

		case 2:
			printf("\ncase 2\n");
			break;

		case 3:
			printf("\ncase 3\n");
			break;

	}

	return 0;

}

/* gives output -
default

case 1

how?
*/

q3-5.c

# include <stdio.h>

int main()
{

	int x=10,y=20,z=5,i;
	i = x<y<z;
	printf("\n%d",i);
	return 0;

}

// how does this gives answer 1?

test.c

#include <stdio.h>

int main() {

	int arr[] = {2,3,4, 1,6};

	printf("\n%d\n%d", arr, sizeof ( arr ));
	return 0;
}


//output - 123445, 20
// books gives 10

you have 100 coins on table, 60 heads and 40 tails. With your eyes closed, how can you separate the coins into 2 groups such that each group has same number of tails.

Then he asked me how you open notepad without using mouse.(simple),then he explain the internal logic behind this like what will happen if you press ctrl+s,ctrl+o etc.

He told me that if he mails me an excel file and when i try to open it, it doesnt open. asked me all the possible reason to it.?

He then told me that if he makes a new web browser and asks me to test it, what all thinks i would test. (again gave me a lot of time to think and tell him as many as i can)

Find 2nd largest element in given array using min. no. of comparisons. I told him solution with 2n comparisions, but he kept insisting me to think more and reduce the comparisons.

An array is given of size m. First n elements (n < m) are filled and rest contains junk. Write code for linear search to find an element x in first n elements. There would be 2 comparisons per iteration: (i < n) in for loop and (arr[i]==x). You have to reduce the no. of comparisons to 1 comparison/iteration.

He asked me to implement a spell checker- first check if it is the correct word and then check words which are similar to the given word. Eg how google shows in Did you mean!

Interviewer : A recursive function has no termination condition. What will happen when it runs.
Me: Stack overflow.

Interviewer: Given a simple recursive function which calls itself:

eg: void f() {
f();
}
How long will it run in your laptop.

Me: I asked for certain assumptions.
1st: what stack space shall I assume?
Interviewer: Half of RAM.(4 GB)

Me: 2nd: I further assumed 4 bytes are required for addressing.

time = (4 GB/ 4 Byte)/frequency; frequency-> processor speed (2.0 GHz)

This is not accurate solution… accuracy involves lot other parameters.
He was just checking my Approach that how I solve the problem.

. Given an array of 1000 elements.Elements are multiplied in a for loop from 1 to thousand.
Time of execution is x milliseconds. How will you reduce x?

There is box and in that box there are real numbers ranging from 1 to 10. What is the probability of getting 2 out of that box.

answer - 0

• how to compile two .cpp codes together.
• what is makefile? utilities?

• difference between #include “” and #include <>.
• what gets included when we do #include?? does it includes the whole definition of the function or just the prototype?

Given 2 sorted arrays , find kth smallest element among them.

Suppose you have a repository of a million records of mobile numbers. A lot of discussion on how will you store these numbers so that you can check whether a given number already exists in minimum space and time complexity?

Given a number say N. WAP to print the next greater number by using the same set of digits of N. For example:

Left shiiting an unsigned int or char by 1 is always equivalent to multiplying it by 2?

• how would you dynamically allocate a 1D array?
• how would you dynamically allocate a 2D array?