add: slice adv. ops. exercises

16-slices/exercises/22-adv-ops-practice/main.go

@@ -0,0 +1,143 @@
+package main
+
+import (
+	s "github.com/inancgumus/prettyslice"
+)
+
+// ---------------------------------------------------------
+// EXERCISE: Practice advanced slice operations
+//
+//  This exercise's intention is warm you up and reinforce
+//  your memory for the advanced slice operations.
+//
+//  Please follow the directions in the following code.
+//
+//  To see the expected output, please run:
+//
+//    go run solution/main.go
+//
+// ---------------------------------------------------------
+
+func main() {
+	//
+	// Use the prettyslice package for printing the slices,
+	// or do it with your own Printf that matches the output
+	// of the prettyslice package.
+	//
+
+	// This allows you to see the backing array of the slices.
+	s.PrintBacking = true
+	// Shows 10 slice elements per line
+	s.MaxPerLine = 10
+	// Prints 60 character per line
+	s.Width = 60
+
+	// ########################################################
+	//
+	// #1: Create a string slice with a length and capacity
+	//     of 5. Call the slice: `names` and print it.
+	//
+
+	// ...
+	// s.Show("1st step", names)
+
+	// ########################################################
+	//
+	// #2: Append the following names to the names slice:
+	//
+	//     "einstein", "tesla", "aristo"
+	//
+	//     Print the names slice.
+	//
+	//     Observe how the slice and its backing array change.
+	//
+
+	// ...
+	// s.Show("2nd step", names)
+
+	// ########################################################
+	//
+	// #3: Fix the append problem by reinitializing the
+	//     names slice below (currently the previous code
+	//     appends after 5 elements).
+	//
+	//     Append the new elements to the head of the names
+	//     slice instead.
+	//
+	//     Print the names slice.
+	//
+	// HINT:
+	//
+	//    The problem is in the `make` function.
+	//
+
+	// ...
+	// s.Show("3rd step", names)
+
+	// ########################################################
+	//
+	// #4: Copy elements from an array to the `names` slice.
+	//
+	//     Currently, `cap(names)` is 5. So, copy only
+	//     the first two elements of the following array
+	//     to the last two elements of the `names` slice.
+	//
+	//     Print the names slice (do not forget extending it).
+	//     You should print 5 elements.
+	//
+	//     Observe how the backing array stays the same.
+	//
+
+	// Array (uncomment):
+	// moreNames := [...]string{"plato", "khayyam", "ptolemy"}
+
+	// ...
+
+	// s.Show("4th step", names)
+
+	// ########################################################
+	//
+	// #5: Clone the `names` slice to the `clone` slice.
+	//
+	//     But only clone (copy) the last 3 elements of the
+	//     `names` slice.
+	//
+	//     Then, append the first two elements of the `names`
+	//     slice to the `clone` slice.
+	//
+	//     Ensure that after appending no new backing array
+	//     allocations occur for the `clone` slice.
+	//
+	//     Print the clone slice before and after the append.
+	//
+
+	// ...
+	// s.Show("5th step (before append)", clone)
+
+	// ...
+	// s.Show("5th step (after append)", clone)
+
+	// ########################################################
+	//
+	// #6: Slice the `clone` slice between 2nd and 4th
+	//     elements.
+	//
+	//     Put the sliced slice into a variable named:
+	//     `sliced`.
+	//
+	//     Append "hypatia" to the `sliced` slice.
+	//
+	//     Ensure that new backing array allocation "happens".
+	//
+	//       Change the 3rd element of the `clone` slice
+	//       to "elder".
+	//
+	//       Doing so should not change any elements of
+	//       the `sliced` slice.
+	//
+	//     Print the `clone` and `sliced` slices.
+	//
+
+	// ...
+	// s.Show("6th step", clone, sliced)
+}