单选题库

int x = 20;
int* p = &x;
*p = *p + 2;

double* p_arr = new double[3];
p_arr[0] = 0.2;
p_arr[1] = 0.5;
p_arr[2] = 0.8;
p_arr += 1;
cout << p_arr[0] << endl;
p_arr -= 1;
delete p_arr;

void func(int& x) {
    x = x * 2;
}

int a = 5;
func(a);

void n_chars(char c, int n) {
    while (n-- > 0)
        cout << c;
}

char my_char = 'w';
int times = 5;
n_chars(my_char, times);

float square(float x) {
    return x * x;
}
float area = square(2);

square(float x) {
    return x * x;
}
float area = square(2);

void square(float x) {
    return x * x;
}
area = square(2.0);

void square(float x) {
    x * x;
    return;
}
area = square(2);