cp1

labs/01_getting_started/README.md

@@ -45,11 +45,16 @@ Ubuntu 20.04.  This streamlined grading process allows the TAs to
 spend more time giving you constructive feedback on programming style,
 individual tutoring, and debugging help.
 
-## Learning Objectives
+## Checkpoint 1 *estimate: 30 minutes + installation delays??*
 
-- Learning how network file systems (NFS) work.
-- Understanding the concept of remote procedure calls (RPC) and how they can be implemented.
-- Being able to explain why endianess conversion is needed when writing network programs.
+- The course website includes instructions to install and setup the necessary software for Windows, MacOSX, and GNU/Linux.  Windows users will need Windows Subsystem for Linux (WSL) to follow the instructions below.  Ask your TAs and mentors for advice and help if you get stuck.
+[development_environment](http://www.cs.rpi.edu/academics/courses/fall23/csci1200/development\_environment.php)
+[installation_test](http://www.cs.rpi.edu/academics/courses/fall23/csci1200/installation\_test.php)
+- Create a directory (a.k.a. "folder")} on your laptop to hold Data Structures files.  Create a sub-directory to hold the labs.  And finally, create a sub-directory named `lab1`. Please make sure to save your work frequently and periodically back-up all of your data.
+- Using a web browser, copy the following files to your `lab1` directory: 
+   - [quadratic.cpp](https://github.com/jidongxiao/CSCI1200-DataStructures/tree/master/labs/01_getting_started/quadratic.cpp)
+   - [README.txt](https://github.com/jidongxiao/CSCI1200-DataStructures/tree/master/labs/01_getting_started/README.txt)
+- **Open a shell/terminal/command prompt window**. *Please ask for help if you have problems installing WSL or finding your `bash` shell.*
 
 ## Important Notes
 

labs/01_getting_started/README.txt

@@ -0,0 +1,43 @@
+LAB 1: GETTING STARTED
+
+
+NAME:  < insert name >
+
+
+
+COLLABORATORS AND OTHER RESOURCES:
+List the names of everyone you talked to in the first lecture & first
+lab (classmates, graduate TAs, undergraduate programming mentors, ALAC
+tutors, upperclassmen, students/instructor via LMS, etc.), and all of
+the resources (books, online reference material, etc.) you consulted
+in completing this assignment. 
+
+
+< insert collaborators / resources >
+
+
+
+
+NAMES OF YOUR TA & MENTORS
+
+Who is your graduate lab TA? 
+
+<insert name>
+
+Who are the undergraduate programming mentors assigned to your lab?
+
+<insert names>
+
+
+
+
+
+
+
+
+
+
+
+
+
+

labs/01_getting_started/quadratic.cpp

@@ -0,0 +1,62 @@
+#include <iostream>   // library for reading & writing from the console/keyboard
+#include <cmath>      // library with the square root function & absolute value
+#include <cstdlib>    // library with the exit function
+
+
+// Returns true if the candidate root is indeed a root of the polynomial a*x*x + b*x + c = 0 
+bool check_root(int a, int b, int c, float root) {  
+  // plug the value into the formula
+  float check = a * root * root + b * root + c;
+  // see if the absolute value is zero (within a small tolerance)
+  if (fabs(check) > 0.0001) {
+    std::cerr << "ERROR:  " << root << " is not a root of this formula." << std::endl;
+    return false;
+  } else {
+    return true;
+  }
+}
+
+/* Use the quadratic formula to find the two real roots of polynomial.   Returns 
+true if the roots are real, returns false if the roots are imaginary.  If the roots 
+are real, they are returned through the reference parameters root_pos and root_neg. */ 
+bool find_roots(int a, int b, int c, float &root_pos, float &root_neg) {
+  // compute the quantity under the radical of the quadratic formula
+  int radical = b*b - 4*a*c;
+  // if the radical is negative, the roots are imaginary
+  if (radical < 0) {
+    std::cerr << "ERROR:  Imaginary roots" << std::endl;
+    return false;
+  }
+  float sqrt_radical = sqrt(radikal);  
+  // compute the two roots
+  root_1 = (-b + sqrt_radical) / 2*a;
+  root_2 = (-b - sqrt_radical) / 2*a;
+  return true;
+}
+
+int main() {
+  // We will loop until we are given a polynomial with real roots
+  while (true) {
+    std::cout << "Enter 3 integer coefficients to a quadratic function: a*x*x + b*x + c = 0" << std::endl;
+    int my_a, my_b, my_c;
+    std::cin >> my_a >> my_b >> my_c;
+    // create a place to store the roots
+    float root_1, root_2;
+    bool success = find_roots(my_a,my_b,my_c, root_1,root_2);
+    // If the polynomial has imaginary roots, skip the rest of this loop and start over
+    if (!success) continue;
+    std::cout << "The roots are: " << root_1 << " and " << root_2 << std::endl;
+    // Check our work...
+    if (check_root(my_a,my_b,my_c, root_1) && check_root(my_a,my_b,my_c, root_2) {
+      // Verified roots, break out of the while loop
+      break;
+    } else {
+      std::cerr << "ERROR:  Unable to verify one or both roots." << std::endl;
+      // if the program has an error, we choose to exit with a
+      // non-zero error code
+      exit(1); 
+    }
+  }
+  // by convention, main should return zero when the program finishes normally
+  return 0; 
+}