c++ - 没有运算符 ">> "匹配这些操作数

Question

我正在编写一个函数定义，让用户输入数组的元素，但出现错误 cin >> a[index];

void show(const double a[], unsigned els) {
    size_t index = 0;

    for (index = 0; index < els; index++) {
        cin >> a[index];
        }

    for (index = 0; index < els; index++) {
        if (a[index] == a[0]) {
            cout << "{" << a[index] << ",";
        }
        else if (a[index] == a[els - 1]) {
            cout << a[index] << "}";
        }
        else { cout << a[index] << ","; }
    }
    cout << endl;
}

Answer 1

在您复制的代码中查看我的注释:

void show(const double a[], unsigned els) {  // a is const
size_t index = 0;

for (index = 0; index < els; index++) {
    cin >> a[index];  // you're trying to write to a const array
    }