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

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?