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import std.stdio;
import std.string;
import std.conv;
import std.typecons;
import std.container : SList;
import std.container : DList;
SList!int stack;
DList!string[string] words;
Nullable!(DList!string) definition;
void push(ref SList!int stack, int value) {
if ( definition.isNull ) {
stack.insertFront(value);
} else {
definition.insertBack(to!string(value));
}
}
int pop(ref SList!int stack) {
auto x = stack.front;
stack.removeFront;
return x;
}
void append(ref Nullable!(DList!string) definition, string token) {
if ( token == ";" ) {
auto wordToBeDefined = definition.front;
if ( wordToBeDefined.isNumeric ) {
throw new Exception("words may not be numeric");
} else {
definition.removeFront;
words[wordToBeDefined] = definition;
definition.nullify;
}
} else {
definition.insertBack(token);
}
}
void evaluate(string word) {
switch ( word ) {
case "ยง":
definition = DList!string();
break;
case "+":
auto a = stack.pop();
auto b = stack.pop();
stack.push(a + b);
break;
case "*":
auto a = stack.pop();
auto b = stack.pop();
stack.push(a * b);
break;
case ".":
writeln(stack.front);
break;
default:
foreach ( token; words[word] ) {
if ( token.isNumeric ) {
stack.push(parse!int(token));
} else {
evaluate(token);
}
}
}
}
void main() {
while ( !stdin.eof ) {
foreach ( token; stdin.readln.split ) {
if ( definition.isNull ) {
if ( token.isNumeric ) {
stack.push(parse!int(token));
} else {
evaluate(token);
}
} else {
definition.append(token);
}
}
}
}
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