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Rust supports explicit partial initialization of arrays by allowing the programmer to specify the initialized elements using the syntax [initialization expression; size]. This syntax allows the programmer to initialize a subset of the elements in the array while leaving the others uninitialized.

For example, if we wanted to initialize the first 3 elements of an array with the value 0 and leave the remaining elements uninitialized, we could use the following code:

let mut arr = [0; 6];

This would create an array of size 6 with the first 3 elements initialized to 0 and the last 3 elements uninitialized.

Alternatively, if we wanted to initialize a specific range of elements in the array, we could use Rust's slicing syntax to extract that range and apply the initialization expression to it. For example, to initialize the elements at indices 2 through 4 in the array, we could use the following code:

let mut arr = [1, 2, 3, 4, 5, 6];
arr[2..5].fill(0);

This would set the elements at indices 2, 3, and 4 to 0 while leaving the other elements unchanged.