Here we will see how to start some third-party application like notepad or anything using C++ program. This program is very simple, we can use command prompt command to do this task. We will pass the application name inside the system() function. This will open it accordingly. ,

Here we will see how to get the memory usage statistics under Linux environment using C++. We can get all of the details from “/proc/self/stat” folder. Here we are taking the virtual memory status, and the resident set size. , ,

Here we will see how to initialize the const type variable using constructor? To initialize the const value using constructor, we have to use the initialize list. This initializer list is used to initialize the data member of a class. The list of members, that will be initialized, will be present after the constructor after colon. members will be separated using comma. , ,

In C++11, the lambda was introduced. Lambdas are basically a part of, that can be nested inside other function call statements. By combining lambda expressions with the auto keyword, they can be used later. In C++14, these lambda expressions are improved. Here we can get the generalized or generic lambda. For example, if we want to create a lambda, that can add integers, add numbers, also c.....

In C++11, we can get the random library to generate random numbers. Here we have used random_device once to seed the random number generator object called mt. This random_device is slower than the mt19937, but we do not need to seed it. It requests for random data to the operating system. , ,

To get attribute list from MongoDB object, you can use for loop to extract key and value for document. Let us create a collection with documents − , Display all documents from a collection with the help of find() method − , This will produce the following output − , Following is the query to get attribute list from MongoDB object − , This will produce the following o.....

Yes, Mongo shell treats numbers as float by default. To work it as int or any other type, you need to mention explicitly. You can use NumberInt() for this. The syntax is as follows − , Let us implement the above syntax in order to treat numbers as integer only (not float) − , Following is the query to display the array value − , This will produce the following output &minu.....

You can use printjson() or print() to get output of MongoDB shell script. Let us create an array of objects. Following is the query to create an array of objects. , Following is the query to get the output of Mongo shell script using printjson() − , This will produce the following output − ,

You can use every() in MongoDB for this. Let us create a collection with documents − , Display all documents from a collection with the help of find() method. The query is as follows − , This will produce the following output − , Following is the query to match each element in a documents array to a condition − , This will produce the following output − ,

Let us create a collection with documents − , Display all documents from a collection with the help of find() method − , This will produce the following output − , Following is the query to select only numeric strings or check whether string is numeric in MongoDB − , This will produce the following output − ,