ajaynitt

/*Find the row with maximum number of 1s
Given a boolean 2D array, where each row is sorted. Find the row with the maximum number of 1s.

Example
Input matrix
0 1 1 1
0 0 1 1
1 1 1 1  // this row has maximum 1s
0 0 0 0

ajaynitt

/*Check if a number is Palindrome
*/
#include <iostream>
#include<cstring>
using namespace std;
#include<cmath>
bool isPalindrome(int n)
	{
	 int ndigit=0;
	 int num=n;

ajaynitt

Input arr[] = [1, 2, 3, 4, 5, 6, 7],
d = 2, n =7
Ans:arr[] = [3, 4, 5, 6, 7, 1, 2]

solution: (Ar Br)r
steps:
first reverse d elements
then reverse remaining (n-d) elements
now reverse entire elements.
Example:

ajaynitt

HOW TO ROTATE A MATRIX 90 DEGREES WITHOUT USING ANY EXTRA SPACE? 
Ans:

O(n^2) time and O(1) space algorithm ( without any workarounds and hanky-panky stuff! )

Rotate by +90:

    Transpose
    Reverse each row

ajaynitt

/* strtok example */
#include <stdio.h>
#include <string.h>

int main ()
{
  char str[] ="- This, a sample string.";
  char * pch;
  printf ("Splitting string \"%s\" into tokens:\n",str);
  pch = strtok (str," ,.-");

ajaynitt

Mutex:
a mutex is locking mechanism used to synchronize access to a resource. Only one task (can be a thread or process based on OS abstraction) can acquire the mutex. It means there will be ownership associated with mutex, and only the owner can release the lock (mutex).
Is a key to a toilet. One person can have the key - occupy the toilet - at the time. When finished, the person gives (frees) the key to the next person in the queue

Semaphore:
Semaphores are typically used as a signaling mechanism between processes.
A typical example is a producer-consumer process pair (not explained here to keep the answer to a readable length).

ajaynitt

/*
class widget
{
  private:
  Bitmap *pb1;//pointer to heap allocated object
  Bitmap *pb2;
};
*/

ajaynitt

//Item 12  from effective c++


//helper function to make a log entry
void logCall(const std::string & name);//make a log entry

//base class
class Customer  
{
  public:

ajaynitt

(1)DECLTYPE:
In the C++ programming language, decltype is a keyword used to query the type of an expression
int i = 33;
decltype(i) j = i*2;
OR
decltype(f) f2 = f; // the type of a lambda function is unique and unnamed


(2)lexical_cast in boost
we can implement like this to server the purpose

ajaynitt

/*
Given an array A[] consisting 0s, 1s and 2s, write a function that sorts A[]. The functions should put all 0s first, then all 1s and all 2s in last.

Example
Input = {0, 1, 1, 0, 1, 2, 1, 2, 0, 0, 0, 1};
Output = {0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2}

soln:Dutch National Flag Algorithm, or 3-way Partitioning —
*/
void sort012(int a[], int arr_size)