73 lines
1.5 KiB
JavaScript
73 lines
1.5 KiB
JavaScript
class TuringMachine {
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constructor(tape = [], rules = [], initialState = "q0", acceptState = "f") {
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this.tape = tape;
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this.rules = this.parseRules(rules);
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this.state = initialState;
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this.head = 0;
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this.acceptState = acceptState;
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this.iteration = 0;
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}
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getStateStatus() {
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return `State: ${this.state}, Step: ${this.iteration}`;
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}
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getHead() {
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return this.head;
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}
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getState() {
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return this.state;
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}
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getTapeAtCell(idx) {
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return this.tape[idx];
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}
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setTapeAtCell(idx, val) {
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this.tape[idx] = val;
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}
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isAccepting() {
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return this.state == this.acceptState;
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}
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parseRules(rules) {
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const parsedRules = {};
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for (const [currentState, readSymbol, action, newState] of rules) {
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const key = `${currentState},${readSymbol}`;
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const value = `${newState},${action}`;
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parsedRules[key] = value;
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}
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return parsedRules;
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}
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step() {
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const currentSymbol = this.tape[this.head];
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const key = `${this.state},${currentSymbol}`;
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if (!(key in this.rules)) {
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return false;
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}
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const rule = this.rules[key];
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const [newState, action] = rule.split(",");
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this.state = newState;
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this.iteration++;
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if (action === "R") {
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this.head += 1;
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} else if (action === "L") {
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this.head -= 1;
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} else {
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this.tape[this.head] = action;
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}
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if (this.isAccepting()) {
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return false;
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}
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return this.head >= 0 && this.head < this.tape.length;
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}
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}
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