Thinking In C++. Volume 2: Practical Programming

         27.             The army wants to recruit people from its selective service list. They have decided to recruit those that signed up for the service in 1997 starting from the oldest down to the youngest. Generate an arbitrary amount of people (give them data members such as age and yearEnrolled) into a vector. Partition the vector so that those who enrolled in 1997 are ordered at the beginning of the list, starting from the youngest to the oldest, and leave the remaining part of the list sorted according to age.

        28.             Make a class called Town with population, altitude, and weather data members. Make the weather an enum with { RAINY, SNOWY, CLOUDY, CLEAR }. Make a class that generates Town objects. Generate town names (whether they make sense or not it doesn’t matter) or pull them off the internet. Ensure that the whole town name is lower case and there are no duplicate names. For simplicity, we recommend keeping your town names to one word. For the population, altitudes, and weather fields, make a generator that will randomly generate weather conditions, populations within the range [100 to 1,000,000) and altitudes between [0, 8000) feet. Fill a vector with your Town objects. Rewrite the vector out to a new file called Towns.txt.

        29.             There was a baby boom, resulting in a 10% population increase in every town. Update your town data using transform( ), rewrite your data back out to file.

        30.             Find the towns with the highest and lowest population. Temporarily implement operator< for your town object for this exercise. Also try implementing a function that returns true if its first parameter is less than its second. Use it as a predicate to call the algorithm you use.

         31.             Find all the towns within the altitudes 2500-3500 feet inclusive. Implement equality operators for the Town class as needed.

        32.             We need to place an airport in a certain altitude, but location is not a problem. Organize your list of towns so that there are no duplicate (duplicate meaning that no two altitudes are within the same 100 ft range. Such classes would include [100, 199), [200, 199), etc. altitudes. Sort this list in ascending order in at least two different ways using the function objects in . Do the same for descending order. Implement relational operators for Town as needed.

        33.             Generate an arbitrary number of random numbers in a stack-based array. Use max_element( ) to find the largest number in array. Swap it with the number at the end of your array. Find the next largest number and place it in the array in the position before the previous number. Continue doing this until all elements have been moved. When the algorithm is complete, you will have a sorted array. (This is a "selection sort".)

        34.             Write a program that will take phone numbers from a file (that also contains names and other suitable information) and change the numbers that begin with 222 to 863. Be sure to save the old numbers. The file format is be as follows:

222 8945

756 3920

222 8432

etc.

        35.             Write a program that given a last name will find everyone with that last name with his or her corresponding phone number. Use the algorithms that deal with ranges (lower_bound, upper_bound, equal_range, etc.). Sort with the last name acting as a primary key and the first name acting as a secondary key. Assume that you will read the names and numbers from a file where the format will be as follows. (Be sure to order them so that the last names are ordered, and the first names are ordered within the last names.):

John Doe             345 9483

Nick Bonham    349 2930

Jane Doe              283 2819

        36.             Given a file with data similar to the following, pull all the state acronyms from the file and put them in a separate file. (Note that you can’t depend on the line number for the type of data. The data is on random lines.)

ALABAMA

AL

AK

ALASKA

ARIZONA

AZ

ARKANSAS

AR

CA

CALIFORNIA

CO

COLORADO

etc.

When complete, you should have a file with all the state acronyms which are:

AL AK AZ AR CA CO CT DE FL GA HI ID IL IN IA KS KY LA ME MD MA MI MN MS MO MT NE NV NH NJ NM NY NC ND OH OK OR PA RI SC SD TN TX UT VT VA WA WV WI WY

         37.             Make an Employee class with two data members: hours and hourlyPay. Employee shall also have a calcSalary( ) function which returns the pay for that employee. Generate random hourly pay and hours for an arbitrary amount of employees. Keep a vector. Find out how much money the company is going to spend for this pay period.

        38.             Race sort( ), partial_sort( ), and nth_element( ) against each other and find out if it’s really worth the time saved to use one of the weaker sorts if they’re all that’s needed.

7: Generic containers