Add presentation; start a different implementation

1 files changed, 85 insertions, 26 deletions

diff --git a/impl/main.cpp b/impl/main.cpp
index 814a3ee..dc6cf45 100644
--- a/impl/main.cpp
+++ b/impl/main.cpp
@@ -1,36 +1,95 @@
-#include "Constant.h"
-#include "Variable.h"
-#include "Min.h"
-#include "Max.h"
-#include "Sum.h"
-#include "Equation.h"
-#include "EquationSystem.h"
-
 #include <iostream>
+#include <vector>
+#include <math.h>
+#include "Expression.h"
+#include "Operator.h"
 
 using namespace std;
 
-int main() {
-  std::map<std::string, int> mappings;
-  mappings["x"] = 10;
+struct Variable : public Operator<float> {
+  Variable(const std::string& x)
+    : _value(x) { }
+  const float eval(const vector<Expression<float> >& v, const map<string, float>& m) const {
+    //assert(v.size() == 0);
+    map<string, float>::const_iterator it = m.find(_value);
+    return (it == m.end() ? -INFINITY : it->second);
+  }
+  private:
+  std::string _value;
+};
+
+struct Const : public Operator<float> {
+  Const(const float& x)
+    : _value(x) { }
+  const float eval(const vector<Expression<float> >& v, const map<string, float>& m) const {
+    //assert(v.size() == 0);
+    return _value;
+  }
+  private:
+  float _value;
+};
+
+struct Mult : public Operator<float> {
+  Mult(const float& x)
+    : _value(x) { }
+  const float eval(const vector<Expression<float> >& v, const map<string, float>& m) const {
+    //assert(v.size() == 1);
+    return _value * v[0].minvalue(m);
+  }
+  private:
+  float _value;
+};
 
-  Equation<int> e(Variable<int>("x"),
-    new Max<int>(
-      new Min<int>(
-        new Constant<int>(100),
-        new Sum<int>(
-          new Variable<int>("x"),
-          new Constant<int>(100))),
-      new Constant<int>(20)));
+struct Maximum : public Operator<float> {
+  const float eval(const vector<Expression<float> >& v, const map<string, float>& m) const {
+    //assert(v.size() == 1);
+    float value = -INFINITY;
+    for (vector<Expression<float> >::const_iterator it = v.begin();
+         it != v.end();
+         ++it) {
+      const float result = it->maxvalue(m);
+      value = (value < result ? result : value);
+    }
+    return value;
+  }
+};
 
-  Equation<int> e2(Variable<int>("x"),
-    new Constant<int>(200));
+struct Minimum : public Operator<float> {
+  const float eval(const vector<Expression<float> >& v, const map<string, float>& m) const {
+    //assert(v.size() == 1);
+    float value = INFINITY;
+    for (vector<Expression<float> >::const_iterator it = v.begin();
+         it != v.end();
+         ++it) {
+      const float result = it->maxvalue(m);
+      value = (value < result ? value : result);
+    }
+    return value;
+  }
+};
 
-  EquationSystem<int> es;
-  es.add(e);
-  es.add(e2);
-  std::map<std::string, int> result = es.solve(mappings);
-  cout << result["x"] << endl;
+int main () {
+  typedef Expression<float> E;
+  typedef vector<E> Args;
+  map<string, float> m;
+  //m["x"] = -10;
+  Args empty;
+  {
+    Args a;
+    {
+      Args b;
+      b.push_back(E(new Const(10), empty));
+      b.push_back(E(new Const(20), empty));
+      b.push_back(E(new Variable("x"), empty));
+      a.push_back(E(new Minimum(), b));
+      cout << E(new Minimum(), b).minvalue(m) << endl;
+    }
+  }
 
+  /*map<string, float> m;
+  vector<Expression<float> > empty;
+  vector<Expression<float> > args;
+  args.push_back(Expression<float>(new Const(10), empty));
+  cout << Expression<float>(new Mult(3), args).minvalue(m) << endl;*/
   return 0;
 }