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@dandelin
Created October 20, 2016 17:12
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#include <iostream>
#include <string>
#include <map>
#include <limits>
#include <functional>
using namespace std;
class Value {
private:
int value;
static int count;
public:
Value() {
value = pseudoRandom();
count++;
}
int pseudoRandom() {
return (count * 42) * (count * 42) / 108;
}
/*
OVERLOAD OPERATORS HERE
(AS A MEMBER)
*/
};
/*
OR HERE
(AS A NON-MEMBER)
*/
bool validate(const map<string, Value> &vMap, string A) {
if (vMap.find(A) == vMap.end()) return false;
else return true;
}
bool validate(const map<string, Value> &vMap, string A, string B) {
if (vMap.find(A) == vMap.end()) return false;
else if (vMap.find(B) == vMap.end()) return false;
else return true;
}
int Value::count = 1;
int main() {
map<string, Value> valueMap;
string command, name;
string left, right;
map<string, function<Value(Value&, Value&)>> binops = {
{ "add", [](Value& leftValue, Value& rightValue)->Value { return leftValue + rightValue; } },
{ "addassign", [](Value& leftValue, Value& rightValue)->Value { return leftValue += rightValue; } }
};
map<string, function<bool(Value&, Value&)>> relops = {
{ "equal", [](Value& leftValue, Value& rightValue)->bool { return leftValue == rightValue; } }
};
map<string, function<Value(Value&)>> unops = {
{ "incpre", [](Value& value)->Value { return ++value; } },
{ "incpost", [](Value& value)->Value { return value++; } },
};
while (true) {
cin >> command;
if (command == "new") {
cin >> name;
valueMap.insert({ name, Value() });
}
else if (command == "add" || command == "addassign") {
cin >> left >> right;
if (validate(valueMap, left, right))
cout << binops[command](valueMap[left], valueMap[right]) << endl;
else
cout << "undefined" << endl;
}
else if (command == "equal") {
cin >> left >> right;
if (validate(valueMap, left, right))
cout << relops[command](valueMap[left], valueMap[right]) << endl;
else
cout << "undefined" << endl;
}
else if (command == "incpre" || command == "incpost") {
cin >> name;
if (validate(valueMap, name))
cout << unops[command](valueMap[name]) << endl;
else
cout << "undefined" << endl;
}
else if (command == "print") {
cin >> name;
if (validate(valueMap, name))
cout << valueMap[name] << endl;
else
cout << "undefined" << endl;
}
else if (command == "printAll") {
for (auto e : valueMap) {
cout << e.first << " : " << e.second << endl;
}
}
else if (command == "end") {
break;
}
else {
cout << "Command is not defined" << endl;
}
cin.ignore(numeric_limits<streamsize>::max(), '\n');
}
return 0;
}
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