Description
PS1-1 Download and read the course syllabus from the Canvas course. (15 pts)
Make sure you can log on to the 24-780 Canvas. Download and read the syllabus. You do not have to
submit anything for this assignment.
PS1-2 Download and install a developing environment. (15 pts)
Follow the instructions on the lecture note and install Visual Studio if you are using Windows, or XCode
if you are using macOS. You can work on assignments on Linux using clang++, in which case you will
need to study how to set up and use clang++ by yourself, or you can come to the instructor office hour
for questions.
PS1-3 Correct Errors in the Count-Down Timer [ps3-1.cpp] (70 pts)
The following code is supposed to take the number of seconds as input and count down until it reaches
zero. When it reaches zero, it prints “Time is up.” But, it includes a bunch of errors. Fix all errors and
make it work.
Pay attention to the compiler error messages. If it says missing semi-colon, then a semi-colon is missing
somewhere. Or, if it says newline in constant, it means constant text string is not closed somewhere.
It is recommended to remove all warnings as well, but it is not required for this assignment.
(The following two paragraphs were missing when I uploaded the document earlier. Sorry)
Save the C++ program as ps1-3.cpp and submit a Zip file that includes the source code (ps1-3.cpp) to the
24-780 Canvas course.
Make sure your code can be compiled by Clang and Visual C++ with no error by one of the compile
servers before submission.
Good luck!
To Answer common questions I had in class:
The count-down output may or may not start the number you entered. And, you may see 0 in the end
or can be 1. But, don’t worry about it. It is ok as long as it counts roughly the number of seconds that
the user enters.
#include <stdio.h>
#include <time.h
// If you are more comfortable with std::cout / std::cin,
// you can replace C-standard library functions with std::cin and std::cout.
int main(void)
{
printf(“24-780 Engineering Computation Problem Set 1-3\n”);
printf(“Enter how many seconds to count:”);
int t;
scanf(“%d”,&t)
int tEnd=time(NULL)+t;
int prev=time(NULL);
while(time(NULL)<tEnd)
{
if(prev!=time(NULL))
{
printf(“%d\n”,tEnd-time(NULL));
prev=time(NULL);
}
printf(“Time is up.\n);
return 0;
}