Description
Programming Part:
Enter data from the file MTA_train_stop_data.txt. The data from this assignment is from
http://www.mta.info/developers/download.html. (Please note that we will only be using some of
the information in this file for this assignment.1
)
In the batch phase you will read all the data from the file called MTA_train_stop_data.txt into a
container of type vector.
Your program will define the class trainStopData. It has the following private member variables :
string stop_id; // id of train stop (1st token)
string stop_name; // name of station (4th token)
double stop_lat; // latitude of train stop location
double stop_lon; // longitude of train stop location
Your class should also have a constructor and the following public member functions:
string get_id( ) const
string get_stop_name( ) const
double get_latitude( ) const
double get_longitude( ) const
1The data is in a common format; please read https://developers.google.com/transit/gtfs/reference?csw=1 for
more information.
Written Part:
The C++ STL has many functions and functors. Here is your chance to try some of them. In a
program when you use an STL algorithm add #include, and when you use an STL
functor add #include.
For many of these problems you will need to look up information online. Here are some sources:
http://en.cppreference.com/w/cpp
http://www.cplusplus.com/reference/algorithm/
http://www.cplusplus.com/reference/std/functional/
http://www.sgi.com/tech/stl/
Fill in the correct code where you see a ****
vector A {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
vector B {1, 2, 1, 2, 1, 2};
vector C{1, 2, 3, 1, 2, 3};
vector D(6);
vector E(10);
1. Copy the first 6 items of vector A into vector D
copy(****, ****, ****);
// D now equals {1, 2, 3, 4, 5, 6}
2. Count the number of ones in vector B
cout << count(****, ****, 1);
//prints out the number of times a one appears in B
3. In C++, there is a way to construct a unary functor from a binary functor. To do this you
use an adapter, a function called bind1st or bind2nd. We use bind1st in this example to
convert the STL binary predicate functor not_equal_to into a unary predicate by setting its
first value to 1.
Count the number of items that are not equal to one in B
cout << count_if(B.begin( ), ****, bind1st(not_equal_to( ), 1));
/*prints out the number of times a one doesn’t appear in B.*/
4. Test to determine if the first 3 items of A are the same as C.
bool same;
same = equal(A.begin( ), ****, ****);
2
5. Find the first item in vector A which equals 5
vector::iterator vecItr;
vecItr = find(****, ****, 5);
// returns an iterator to 5 in vector A
if (vecItr != A.end( ))
cout << ****;
// prints out the value pointed to by vecItr
6. Find the first item in C that is greater than 2
vecItr = find_if(****, ****, bind2nd(greater(), 2));
// returns an iterator to 3 in C
if (vecItr != C.end( ))
cout << ****;
// prints out the value pointed to by vecItr
3
