单选题库

int gcd(int a, int b) {
    int big = a > b ? a : b;
    int small = a < b ? a : b;
    if (big % small == 0) {
        return small;
    }
    return gcd(small, big % small);
}

int fibA(int n) {
    if (n <= 1) return n;
    int f1 = 0, f2 = 1;
    for (int i = 2; i <= n; ++i) {
        int temp = f2;
        f2 = f1 + f2;
        f1 = temp;
    }
    return f2;
}
 
int fibB(int n) {
    if (n <= 1) return n;
    return fibB(n - 1) + fibB(n - 2);
}

struct ListNode {
    int val;
    ListNode* next;
    ListNode(int val):val(val), next(nullptr){}
};
 
void removeElements(ListNode* head, int val) {
    if (head == nullptr) {
        return;
    }
    ListNode* cur;
    ListNode* dummyHead = new ListNode(0); //虚拟头节点
    ________________________________    // 在此处填入代码
 
    while(cur ->next != nullptr) {
        if(cur->next->val == val) {
            ListNode* tmp = cur->next;
            cur->next = cur->next->next;
            delete tmp;
            tmp = nullptr;
        }
        else {
            cur = cur ->next;
        }
    }
    head = dummyHead->next;
    delete dummyHead;
    dummyHead = nullptr;
}