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1. What does this program print? ``

cpp
#include <iostream>

struct Node {
    int value;
    Node* next;
};

void print_list(const Node* head) {
    for (const Node* cur = head; cur != nullptr; cur = cur->next) {
        std::cout << cur->value << " ";
    }
    std::cout << "\n";
}

int main() {
    Node c{3, nullptr};
    Node b{2, &c};
    Node a{1, &b};
    Node* head = &a;

    Node* first = head;
    Node* second = head->next;
    first->next = second->next;
    second->next = first;
    head = second;

    print_list(head);
    return 0;
}

``

1 32 1 31 2 32 3

2. In a pointer diagram, which arrow does the statement a.next = b.next; move?

The arrow from head, because head points at a.The arrow from b, so that b skips over c.The arrow from a, so that it points at whatever b.next points at.The arrow from c, which now points back at a.

3. What does this program print? Write the two output lines separated by / . ``

cpp
#include <iostream>
#include <vector>

int main() {
    std::vector<int> prices{10, 20, 30};
    for (auto p : prices) p += 1;
    std::cout << prices[0] << ' ';

    for (auto& p : prices) p += 1;
    std::cout << prices[0] << ' ' << prices[2] << '\n';

    std::vector<int> copy = prices;
    copy[1] = 0;
    std::cout << prices[1] << ' ' << copy[1] << '\n';
    return 0;
}

``

11 11 31 / 21 010 11 31 / 21 010 11 31 / 0 010 11 31 / 20 0

4. In the declaration std::vector<int>& alias = original;, which symbol makes alias a second name for original instead of a copy? Type the symbol.

Type your answer.

5. What does this program print? ``

cpp
#include <iostream>

int main() {
    int x = 10;
    int& r = x;
    int* p = &x;
    int y = r;
    r = 20;
    *p += 5;
    std::cout << x << ' ' << y << ' ' << r << '\n';
    return 0;
}

``

25 20 2515 10 1510 10 2025 10 25

Diagrams and aliasing