Problem You have the following database table: employee (emp_name, emp_age, emp_department) Write an SQL statement to calculate the average age of employees who are older than 30 years old for each department. Do not display the average if the number of employees used in the calculation is less than 3. Solution You need to use
Problem Develop an algorithm to print the first none repeating character in a string for example the first none repeating character in the string “baby” is “a” Hash character in string This is a typical interview question. A better solution to solve this problem in linear time is to use a hash table on the
Find non repeating character string Develop an algorithm to print the first none repeating character in a string for example the first none repeating character in the string “baby” is “a” Algorithm A brute force method requires us to use two nested loops for character comparison. The moment we find a match we break the
Problem Write a C++ function that takes a character as input and returns true if the second significant bit of the binary representation of the character is set (i.e equals to 1) otherwise return false. Solution This is a bitwise operations problem. First you need to shift the character one digit to the right then
Activity selection problem greedy algorithm Assume that you are an administrator who is in charge of a conference room equipped with some expensive telepresence system. Different employees or groups of employees need to have access to the conference room but they can not use the telepresence system at the same time. Every day employees who
Maximal independent set problem You have a set of radio stations all having the same transmission frequency. Signals from adjacent stations interfere with each other which causes data loss. We need to choose the largest set of stations that can operate at the same time without data loss. Assume the list of stations is represented
Running time of nested loop Given the following pattern matching algorithm which decides whether there is an occurrence of a pattern of size (m) in a text of size (n). The algorithm compares the pattern in a given location in the text checking all characters from left to right. (1) Assuming (m) is much smaller
Problem You have the following function signature int Contains(char* s1, char* s2, int n1, int n2) where s1, s2 are two strings and n1, n2 are their respective lengths. The function should return 1 if the s1 contains s2 otherwise it returns 0. For example if s1 = abcdefg and s2 = acg then it
Problem Write code to simulate the SQL statement “Select unique emp_name from employees” Solution Assuming we have an array of employee names we need to write a function that prints the unique employee names in the array. We can use a built in hash table for that matter. Just hash all names then print the
Problem Write a C++ function to check string for repeated characters. Algorithm Using brute force we can start with the first character then compare it to the rest of the characters. If we can find a match then the string does have repeated characters otherwise we move to the next character and so on. If
