ABB R&D Engineer Interview Questions and Answers

Connecting to a database has multiple options depending on the type of database and programming language used.

• For SQL databases, options include using JDBC for Java, ODBC for C++, and ADO.NET for C#.

• For NoSQL databases, options include using MongoDB's driver for Python or Node.js.

• ORMs like Hibernate and Entity Framework can also be used to abstract away the database connection details.

• Connection strings are used to spe...read more

Implement stack data structure

• Use an array or linked list to store elements

• Push operation adds element to top of stack

• Pop operation removes element from top of stack

• Peek operation returns top element without removing it

Global variables are accessible from any part of the program and can be modified by any function.

• Global variables are declared outside of any function.

• They can be accessed and modified by any function in the program.

• If a function modifies the value of a global variable, the new value is visible to all other functions.

• Global variables can be useful for sharing data between functions.

• However, overuse of global variables

Program to transpose a matrix

• Iterate through rows and columns of the matrix

• Swap the elements at (i,j) and (j,i) positions

• Return the transposed matrix

Pre and post fix operators are used to increment or decrement a value before or after it is used in an expression.

• Pre-fix operator (++x) increments the value of x and returns the new value.

• Post-fix operator (x++) returns the value of x and then increments it.

• Both operators can be used with variables of numeric data types.

• They can also be used with pointers to increment or decrement the memory address they point to.