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fix: map quiz

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Inanc Gumus
2019-05-06 14:45:20 +03:00
parent 5c6b606da8
commit 9ee5f8e0ba
1 changed files with 6 additions and 6 deletions
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22-maps/questions/README.md
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@ -1,5 +1,5 @@
## Why are maps used? ## Why are maps used for?
For example, here is a program that uses a slice to find an element among millions of elements. For example, here is an inefficient program that uses a loop to find an element among millions of elements.
```go ```go
millions := []int{/* millions of elements */} millions := []int{/* millions of elements */}
for _, v := range millions { for _, v := range millions {
@ -17,7 +17,7 @@ for _, v := range millions {
> **2:** Map doesn't work in O(n) time for key lookup. > **2:** Map doesn't work in O(n) time for key lookup.
> >
## When shouldn't you use a map? ## When should you not use a map?
1. To find an element through a key 1. To find an element through a key
2. To loop over the map keys *CORRECT* 2. To loop over the map keys *CORRECT*
3. To add structured data to your program 3. To add structured data to your program
@ -39,19 +39,19 @@ for _, v := range millions {
> **5:** Slices, maps, and function values are not comparable. So, they cannot be map keys. > **5:** Slices, maps, and function values are not comparable. So, they cannot be map keys.
> >
## Which are the following map's key and element types? ## Which are the key and element types of the map below?
```go ```go
map[string]map[int]bool map[string]map[int]bool
``` ```
1. Key: string Element: bool 1. Key: string Element: bool
2. Key: string Element: int 2. Key: string Element: int
3. Key: string Element: map[int] 3. Key: string Element: map[int]
4. Key: string Element: map[int]string *CORRECT* 4. Key: string Element: map[int]bool *CORRECT*
> **4:** The map contains other maps. The element type of a map can be of any type. > **4:** The map contains other maps. The element type of a map can be of any type.
> >
## What is a map behind the scenes? ## What is a map value behind the scenes?
1. A map header 1. A map header
2. A pointer to a map header *CORRECT* 2. A pointer to a map header *CORRECT*
3. Tiny data structure with 3 fields: Pointer, Length and Capacity 3. Tiny data structure with 3 fields: Pointer, Length and Capacity