Pass by address

Name: ____________________________________________________ Alpha: _____________ Section: ________

Describe help received: _________________________________________________________________

See the bottom for how to submit your work.

Due: Before 0800 on next class day

(10 pts) Read today's lecture notes. Honestly declare how you read the notes.
1. (10 pts) I read the notes carefully. I have a good understanding of the topics therein.
2. (10 pts) I read the notes carefully, but I don't really understand the following points well:
3. (0 pts) I didn't read the notes carefully.

[10pts] What will be the output of the following program? A similar question will appear in the exam. See if you can do this manually.


#include <iostream>
using namespace std; 

int foo(double x, double* y);

int main() 
{
  double a = 8.5;
  double b = 10.1;
  cout << "ONE " << foo(a, &b) << endl;
  cout << "TWO " << a << " " << b << endl;
  return 0;
}

int foo(double x, double* y) 
{
  x = x + 2;
  *y = *y + 2;
  cout << "THREE " << x << " " << (*y) << endl;  
  return x;
}

Give the output:

[80pts] Download hw.cpp. The program contains a main which reads in two candidate names, then reads in a bunch of votes, and finally says who won or if there was a tie.

You must not change main(), but should complete the prototypes and definitions of the functions needed for the program to work. In particular, you will need to define (at least) the three functions get_names, update_counts, and display_results.

Here is a brief description of each function. Of course, the best way to understand how each function needs to work is by looking at the code in hw.cpp that uses these functions, and the sample runs below.

get_names displays a prompt and then reads in two strings from the terminal for the two candidate names. These are copied into the two strings which are passed to the function as arguments.
update_counts takes a single name that was entered, the two candidate names, and pointers to the two current counts. If the given name is "END", update_counts should return false. Otherwise rhe function compares the first name against each candidate name, and if it matches, it updates the corresponding count and returns true. If the provided name doesn't match either candidate's name, update_counts should print an error message to the terminal and return true.
display_results takes in both candidate names and counts, and displays which candidate won as well as the vote total. If both counts are the same it just prints "Tie!".

Here are some sample runs (user input in green):

~$ ./hw
Candidate names: Pepsi Coke
Enter votes, ending with "END":
Pepsi
Pepsi
Coke
Coke
Coke
Pepsi
Coke
END
Coke wins with 4 of 7 votes

~$ ./hw
Candidate names: IT CS
Enter votes, ending with "END":
IT
CS
CS
IT
Aero
Invalid name
IT
IT
CS
CS
EE
Invalid name
END
Tie!

~$ ./hw
Candidate names: Tacos Sushi
Enter votes, ending with "END":
Tacos
Pizza
Invalid name
Sushi
Tacos
END
Tacos wins with 2 of 3 votes

Submit to the submission server (due: 0800 on the next class day)

 ~/bin/submit -c=IC210 -p=hw18 hw.cpp

Bring to class

A printout of this homework sheet annotated with your answers
The codeprint of hw.cpp.