feat: added c++ grader example

README.md

@@ -4,6 +4,8 @@ Example grading scripts for RamDesk
 * C assignment with Python grader
     * [Sum](c_assignment_python_grader/sum/README.md)
     * [Factorial](c_assignment_python_grader/factorial/README.md)
+* C++ assignment with C++ grader
+    * [Triangle](c++_assignment_c++_grader/triangle/README.md)
 * C++ assignment with table grader
     * [Reverse String](c++_assignment_table_grader/reverse_string/README.md)
 * Java assignment with Java grader

c++_assignment_c++_grader/triangle/README.md

@@ -0,0 +1,34 @@
+# Triangle (C++)
+
+[< Home](../../README.md)
+
+Given the file `triangle.h`, write the implementation for the `Triangle` class inside `triangle.cpp`.
+
+
+### Examples
+
+```bash
+./triangle
+# Triangle
+# Sides: 37.7156, 31.4852, 25.288
+# Perimeter: 94.4888
+# Area: 394.677
+# Equilateral: 0
+# Isosceles: 0
+# Scalene: 1
+# Test passed
+# ...
+```
+
+
+### Grade command
+
+This is the command to set up the grader in RamDesk.
+
+```bash
+./triangle
+```
+
+### RamDesk Grade Configuration
+
+Make sure to enble the task "Make" with location "Root".

c++_assignment_c++_grader/triangle/grader/Makefile

@@ -0,0 +1,2 @@
+triangle: triangle.h sub/triangle.cpp
+	g++ -I. main.cpp sub/triangle.cpp -o triangle

c++_assignment_c++_grader/triangle/grader/main.cpp

@@ -0,0 +1,94 @@
+#include "triangle.h"
+
+#include <cmath>
+#include <cstdlib>
+#include <iostream>
+
+
+double get_perimeter(double s1, double s2, double s3) {
+    return s1 + s2 + s3;
+}
+
+double get_area(double s1, double s2, double s3) {
+    double s = (s1 + s2 + s3) / 2.0;
+    return std::sqrt(s * (s - s1) * (s - s2) * (s - s3));
+}
+
+bool is_equilateral(double s1, double s2, double s3) {
+    return s1 == s2 && s2 == s3;
+}
+
+bool is_isosceles(double s1, double s2, double s3) {
+    return s1 == s2 || s1 == s3 || s2 == s3;
+}
+
+bool is_scalene(double s1, double s2, double s3) {
+    return s1 != s2 && s1 != s3 && s2 != s3;
+}
+
+double random_side()
+{
+    return 1.0 + (double) rand() / RAND_MAX * 99.0;
+}
+
+bool prob(double p)
+{
+    return (double) rand() / RAND_MAX < p;
+}
+
+int test(){
+    double s1;
+    double s2;
+    double s3;
+    double area;
+    do {
+        s1 = random_side();
+        s2 = random_side();
+        s3 = random_side();
+        if (prob(0.3)) { // make it isosceles
+            s2 = s1;
+        }
+        if (prob(0.3)) { // make it equilateral
+            s3 = s1;
+        }
+        area = get_area(s1, s2, s3);
+    } while (area != area); // make sure it's a valid triangle
+
+    Triangle t(s1, s2, s3);
+    t.print();
+
+    int score = 0;
+    if (t.get_perimeter() == get_perimeter(s1, s2, s3)) {
+        score += 1;
+    }
+    if (t.get_area() == get_area(s1, s2, s3)) {
+        score += 1;
+    }
+    if (t.is_equilateral() == is_equilateral(s1, s2, s3)) {
+        score += 1;
+    }
+    if (t.is_isosceles() == is_isosceles(s1, s2, s3)) {
+        score += 1;
+    }
+    if (t.is_scalene() == is_scalene(s1, s2, s3)) {
+        score += 1;
+    }
+
+    if (score == 5) {
+        std::cout << "Test passed" << std::endl;
+    } else {
+        std::cout << "Test failed" << std::endl;
+    }
+    return score;
+}
+
+
+int main() {
+    srand(time(0));
+    int score = 0;
+    for (int i = 0; i < 20; i++) {
+        score += test();
+    }
+    std::cout << score << std::endl;
+    return 0;
+}

c++_assignment_c++_grader/triangle/grader/triangle.h

@@ -0,0 +1,28 @@
+#ifndef TRIANGLE_H
+#define TRIANGLE_H
+
+#include <iostream>
+
+class Triangle {
+private:
+    double side1, side2, side3;
+
+public:
+    Triangle(double s1, double s2, double s3);
+    double get_perimeter() const;
+    double get_area() const;
+    bool is_equilateral() const;
+    bool is_isosceles() const;
+    bool is_scalene() const;
+    void print() const {
+        std::cout << "Triangle" << std::endl;
+        std::cout << "Sides: " << side1 << ", " << side2 << ", " << side3 << std::endl;
+        std::cout << "Perimeter: " << get_perimeter() << std::endl;
+        std::cout << "Area: " << get_area() << std::endl;
+        std::cout << "Equilateral: " << is_equilateral() << std::endl;
+        std::cout << "Isosceles: " << is_isosceles() << std::endl;
+        std::cout << "Scalene: " << is_scalene() << std::endl;
+    }
+};
+
+#endif

c++_assignment_c++_grader/triangle/solution/triangle.cpp

@@ -0,0 +1,29 @@
+#include "triangle.h"
+
+#include <cmath>
+#include <iostream>
+
+
+Triangle::Triangle(double s1, double s2, double s3)
+    : side1(s1), side2(s2), side3(s3) {}
+
+double Triangle::get_perimeter() const {
+    return side1 + side2 + side3;
+}
+
+double Triangle::get_area() const {
+    double s = get_perimeter() / 2.0;
+    return std::sqrt(s * (s - side1) * (s - side2) * (s - side3));
+}
+
+bool Triangle::is_equilateral() const {
+    return side1 == side2 && side2 == side3;
+}
+
+bool Triangle::is_isosceles() const {
+    return side1 == side2 || side1 == side3 || side2 == side3;
+}
+
+bool Triangle::is_scalene() const {
+    return side1 != side2 && side1 != side3 && side2 != side3;
+}