A ____ statement provides a simple method for creating a new and typically shorter name for an existing structure type.

Customizable mini-programs that display continuously updated information in the Windows Sidebar are called ________

Fill in the blank(s) with correct word

Find the error(s) in each of the following program segments, and explain how the error(s) can be corrected :

``` int sum(int n) { // assume n is nonnegative if (0 == n) return 0; else n + sum(n - 1); } ```