2 files changed, 57 insertions, 1 deletions

diff --git a/script.cpp b/script.cpp
index 689066f..b3b179b 100644
--- a/script.cpp
+++ b/script.cpp
@@ -1,4 +1,5 @@
 #include "script.h"
+#include <functional>
 
 bool validateExprNodeType(ExprNodeType type){
 	return type>=EFN_ADD&&type<=EFN_INVALID;
@@ -41,8 +42,61 @@ pair<ExprFunction,int> parseExprFunction(const string &s,int start=0){
 }*/
 
 
+function<int(int, int)> exprnode_functions[]{
+	[](int a,int b){return a +  b;  },
+	[](int a,int b){return a -  b;  },
+	[](int a,int b){return a *  b;  },
+	[](int a,int b){return a /  b;  },
+	[](int a,int b){return a %  b;  },
+	[](int a,int b){return a == b;  },
+	[](int a,int b){return a != b;  },
+	[](int a,int b){return a <  b;  },
+	[](int a,int b){return a >  b;  },
+	[](int a,int b){return a <= b;  },
+	[](int a,int b){return a >= b;  },
+	[](int a,int b){return a && b;  },
+	[](int a,int b){return a || b;  },
+	[](int _,int b){return !b;      },
+	[](int a,int b){return max(a,b);},
+	[](int a,int b){return min(a,b);},
+};
+
+
+
 int Expression::evaluate(unordered_map<string,QueryResult> &vars){
-	;
+	if(type<0||type>=EFN_INVALID)return -42;
+	if((type==EFN_NUMBER||type==EFN_VARIABLE)&&args.size()!=0)return -43;
+	if(type==EFN_NUMBER)return intval;
+	if(type==EFN_VARIABLE)return vars[varname].res;
+
+	if((type==EFN_MAX||type==EFN_MIN)&&args.size()==0)return -44;
+	if(type==EFN_MAX){
+		int maxval=args[0].evaluate(vars),maxat=0,i,v;
+		for(i=1;i<args.size();i++){
+			v=args[i].evaluate(vars);
+			if(v>maxval){
+				maxval=v;
+				maxat=i;
+			}
+		}
+		return maxval;
+	}
+	if(type==EFN_MIN){
+		int minval=args[0].evaluate(vars),minat=0,i,v;
+		for(i=1;i<args.size();i++){
+			v=args[i].evaluate(vars);
+			if(v>minval){
+				minval=v;
+				minat=i;
+			}
+		}
+		return minval;
+	}
+
+	if(args.size()!=1)return -45;
+	if(type==EFN_NOT)return exprnode_functions[EFN_NOT](0,args[0].evaluate(vars));
+	if(args.size()!=2)return -46;
+	return exprnode_functions[type](args[0].evaluate(vars),args[1].evaluate(vars));
 }
 
 
diff --git a/script.h b/script.h
index 05427ca..393bb45 100644
--- a/script.h
+++ b/script.h
@@ -27,6 +27,8 @@ bool validateExprNodeType(ExprNodeType);
 struct Expression {
 	ExprNodeType type;
 	vector<Expression> args;
+	int intval;
+	string varname;
 	int evaluate(unordered_map<string,QueryResult>&);
 };