??? ??? ??? ??? ???, ?? ??, ?? ?? ??, ??? ????? ?? ??? ?? ?????. ??? ??? ?? ??? ????? ?? ?? ??? ?? ??? ?? ???? ???? ??? ? ????. ?? ???? ?? ??? ??????? ?? ??? ??? ???? ??? ?? ?? ???? ???? ?? ????. ? ????? JavaScript? ??? ???? ?? ????? ?? ?????? ???? ??? ?? ??? ???? ?????.

---

??? ???? ???? ??? ??????

??? ???? ????? ??? ?? ?? ??? ????.

1. ?? ????: ?? ?? ??? ?? ??? ???? ?? ????? ??? ? ????. ??? ??? ???? ? ??? ?? ? ????.
2. ???: ?? ???? ?? ??? ?? ???? ? ?? ????? ???? ???? ????? ??? ???? ? ????.
3. ? ?? ??: ??? ??? ???? ?? ???? ??? ?? ???? ??? ? ????? ??? ? ????.

---

??? ???? ??? ???? ???? ?? ???

??? ???? ?? ??? ?? ??? ??? ? ???? ?? ??? ??? ??? ????(?: ?? ??, ??? ?? ?? ??? ??)?? ???? ?????. ??? ??? ????? ??? ? ?? ??? ??????.

---

?? ???

1. ????(??)

function recursiveFunction(args) {
    // Base case
    if (baseCondition) {
        // Handle the base case
        return;
    }

    // Recursive calls
    for (let i = 0; i < someLimit; i++) {
        recursiveFunction(newArgs);
    }
}

2. ??? ??? ?? ??

?? ?? ??? ?? ??? ????? ?? ??? ????.

function iterativeFunction(args) {
    // Initialize the stack
    let stack = [initialState];

    // Loop until the stack is empty
    while (stack.length > 0) {
        // Pop the current state from the stack
        let currentState = stack.pop();

        // Handle the base case (optional, since we can check on each iteration)
        if (baseCondition) {
            continue;  // Skip or handle the base case
        }

        // Process the current state
        processState(currentState);

        // Push next states onto the stack
        for (let i = 0; i < someLimit; i++) {
            let newState = generateNewState(currentState, i);
            stack.push(newState);
        }
    }
}

---

??? ??

1. ?? ???:
   
   ??? ?? ??? ?????? ??, ?? ?? ?? ?? ??? ? ?? ??? ? ????.

2. ??? ?? ??:
   
   ??? ?? ???? ??? ?? ??? ???? ??? ?? ? ??? ?????.

3. ?? ?? ??:
   
   ???? ?? ??? ?? ??? ???? ?????. ?? ?? ????? ?? ??? ??? ??? ??? ? ????. ?? ??? ???? ???? ?? ??? ????? ???.

4. ?? ?? ??:
   
   ?? ??? ??? ?????(?? ?? ???? ???? ??? ??).

5. ?? ?? ??:
   
   ?? ??? ??? ?? ??? ???? ??? ????? ?? ??(?: ??? ?? ?? ?? ??)? ??? ?????.

---

?? ?: ???? ?? ??

?? ??:

function recursiveFunction(args) {
    // Base case
    if (baseCondition) {
        // Handle the base case
        return;
    }

    // Recursive calls
    for (let i = 0; i < someLimit; i++) {
        recursiveFunction(newArgs);
    }
}

??? ??? ?? ??:

function iterativeFunction(args) {
    // Initialize the stack
    let stack = [initialState];

    // Loop until the stack is empty
    while (stack.length > 0) {
        // Pop the current state from the stack
        let currentState = stack.pop();

        // Handle the base case (optional, since we can check on each iteration)
        if (baseCondition) {
            continue;  // Skip or handle the base case
        }

        // Process the current state
        processState(currentState);

        // Push next states onto the stack
        for (let i = 0; i < someLimit; i++) {
            let newState = generateNewState(currentState, i);
            stack.push(newState);
        }
    }
}

---

??? ???? ???? ?

?? 1: ???? ?? ?? ??(DFS)

?? ?? ??(DFS)? ????? ??? ???? ?????. ?? DFS ????? ??? ????.

function inorderTraversal(root) {
    if (root === null) return;
    inorderTraversal(root.left);
    console.log(root.value);
    inorderTraversal(root.right);
}

??? ??? ?? ??:

function inorderTraversalIterative(root) {
    let stack = [];
    let current = root;

    while (stack.length > 0 || current !== null) {
        // Reach the leftmost node
        while (current !== null) {
            stack.push(current);
            current = current.left;
        }

        // Visit the node
        current = stack.pop();
        console.log(current.value);

        // Move to the right node
        current = current.right;
    }
}

? ???? ??? ??? ??? ????? ???? ??? ??? ???? ?? ??? ????????.

---

? 2: ???? ?? ??(??)

?? ??? ?? ??? ????? ????? ?????. ?? ??? ??? ????.

function dfs(graph, node, visited = new Set()) {
    if (visited.has(node)) return;
    console.log(node);
    visited.add(node);

    for (let neighbor of graph[node]) {
        dfs(graph, neighbor, visited);
    }
}

??? ??? ?? ??:

function dfsIterative(graph, startNode) {
    let stack = [startNode];
    let visited = new Set();

    while (stack.length > 0) {
        let node = stack.pop();

        if (visited.has(node)) continue;

        console.log(node);
        visited.add(node);

        // Add neighbors to the stack in reverse order to maintain DFS order
        for (let neighbor of graph[node].reverse()) {
            if (!visited.has(neighbor)) {
                stack.push(neighbor);
            }
        }
    }
}

? ?? ??? ??? ??? ???? ? ??? ?? ?? ??? ?? ?? ??? ??? ??? ??? ??? ?? ?????.

---

? 3: ?? ?? ??(???)

??? ?? ??? ???? ?? ??? ?? ??? ??? ?? ????? ??? ? ????.

function inorderTraversal(root) {
    if (root === null) return;
    inorderTraversal(root.left);
    console.log(root.value);
    inorderTraversal(root.right);
}

??? ??? ?? ??:

function inorderTraversalIterative(root) {
    let stack = [];
    let current = root;

    while (stack.length > 0 || current !== null) {
        // Reach the leftmost node
        while (current !== null) {
            stack.push(current);
            current = current.left;
        }

        // Visit the node
        current = stack.pop();
        console.log(current.value);

        // Move to the right node
        current = current.right;
    }
}

?? ??? ??? ???? ?? ?? ??? ????????. currentSubset? ???? ???? ??? ? ??? ???? ???? ?????.

---

? 4: ?? ??

??? ?? ??? ????? ????? ??? ?????.

function subsets(nums) {
    let result = [];
    function backtrack(start, currentSubset) {
        result.push([...currentSubset]);
        for (let i = start; i < nums.length; i++) {
            currentSubset.push(nums[i]);
            backtrack(i + 1, currentSubset);
            currentSubset.pop();
        }
    }
    backtrack(0, []);
    return result;
}

??? ??? ?? ??:

function subsetsIterative(nums) {
    let stack = [{start: 0, currentSubset: []}];
    let result = [];

    while (stack.length > 0) {
        let { start, currentSubset } = stack.pop();
        result.push([...currentSubset]);

        // Explore subsets by including elements from `start` onwards
        for (let i = start; i < nums.length; i++) {
            currentSubset.push(nums[i]);
            stack.push({ start: i + 1, currentSubset: [...currentSubset] });
            currentSubset.pop(); // backtrack
        }
    }

    return result;
}

? ?? ??? ??? ???? ??? ?? ??? ?????. ???? ???? ??? ???? ??? ?????.

---

?? 5: N-Queens ??(???)

N-Queens ??? ?? ???? ???? ???? ??? ????.

function permute(nums) {
    let result = [];
    function backtrack(start) {
        if (start === nums.length) {
            result.push([...nums]);
            return;
        }
        for (let i = start; i < nums.length; i++) {
            [nums[start], nums[i]] = [nums[i], nums[start]];  // swap
            backtrack(start + 1);
            [nums[start], nums[i]] = [nums[i], nums[start]];  // backtrack (swap back)
        }
    }
    backtrack(0);
    return result;
}

??? ??? ?? ??:

function recursiveFunction(args) {
    // Base case
    if (baseCondition) {
        // Handle the base case
        return;
    }

    // Recursive calls
    for (let i = 0; i < someLimit; i++) {
        recursiveFunction(newArgs);
    }
}

---

??

??? ???? ??? ???? ???? ?? ?? ????, ?? ??? ?? ??/??? ??? ??? ????? ??? ?????. ??? ??? ???? ?? ??? ???? ?? ??? ???? ???? ???? ??? ? ????? ??? ? ????. ??? ?? ??? ???? ??? ??? ???? ? ??? ?? ??? ??? ???.

? ??? ??? ???? ??? ???? ??: ?? ???? ?? ?????. ??? ??? PHP ??? ????? ?? ?? ??? ?????!