void insertion_sort(vector<int> &nums) {
    for (int i = 1; i < nums.size(); i++) {
        int base = nums[i], j = i - 1;

        ______________________________ {    // 在此处填入代码
            nums[j + 1] = nums[j];
            j--;
        }
        nums[j + 1] = base;
    }
}