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