How to make tail function return what I need?
I need to encode list in OCaml. Command: encode ['a','a','b','b','b','c'];; have to return [(2,'a');(3,'b');(1,'c')]
Now I have this function:
let encode list =
let rec encodeHelper list acc = match list with
| ->
| head :: -> (1, head) ::
| head :: headNext :: tail -> if (head = headNext) then encodeHelper (headNext :: tail) (acc + 1)
else (acc, head) :: encodeHelper (headNext :: tail) acc
in encodeHelper list 1
;;
But it returns:
- : (int * (char * char * char * char * char * char)) list =
[(1, ('a', 'a', 'b', 'b', 'b', 'c'))]
function functional-programming ocaml
asked Nov 13 '18 at 19:04
IlyaIlya
335
add a comment |
I need to encode list in OCaml. Command: encode ['a','a','b','b','b','c'];; have to return [(2,'a');(3,'b');(1,'c')]
Now I have this function:
let encode list =
let rec encodeHelper list acc = match list with
| ->
| head :: -> (1, head) ::
| head :: headNext :: tail -> if (head = headNext) then encodeHelper (headNext :: tail) (acc + 1)
else (acc, head) :: encodeHelper (headNext :: tail) acc
in encodeHelper list 1
;;
But it returns:
- : (int * (char * char * char * char * char * char)) list =
[(1, ('a', 'a', 'b', 'b', 'b', 'c'))]
function functional-programming ocaml
asked Nov 13 '18 at 19:04
IlyaIlya
335
add a comment |
I need to encode list in OCaml. Command: encode ['a','a','b','b','b','c'];; have to return [(2,'a');(3,'b');(1,'c')]
Now I have this function:
let encode list =
let rec encodeHelper list acc = match list with
| ->
| head :: -> (1, head) ::
| head :: headNext :: tail -> if (head = headNext) then encodeHelper (headNext :: tail) (acc + 1)
else (acc, head) :: encodeHelper (headNext :: tail) acc
in encodeHelper list 1
;;
But it returns:
- : (int * (char * char * char * char * char * char)) list =
[(1, ('a', 'a', 'b', 'b', 'b', 'c'))]
function functional-programming ocaml
asked Nov 13 '18 at 19:04
IlyaIlya
335
I need to encode list in OCaml. Command: encode ['a','a','b','b','b','c'];; have to return [(2,'a');(3,'b');(1,'c')]
Now I have this function:
let encode list =
let rec encodeHelper list acc = match list with
| ->
| head :: -> (1, head) ::
| head :: headNext :: tail -> if (head = headNext) then encodeHelper (headNext :: tail) (acc + 1)
else (acc, head) :: encodeHelper (headNext :: tail) acc
in encodeHelper list 1
;;
But it returns:
- : (int * (char * char * char * char * char * char)) list =
[(1, ('a', 'a', 'b', 'b', 'b', 'c'))]
function functional-programming ocaml
function functional-programming ocaml
asked Nov 13 '18 at 19:04
IlyaIlya
335
asked Nov 13 '18 at 19:04
IlyaIlya
335
asked Nov 13 '18 at 19:04
IlyaIlya
335
asked Nov 13 '18 at 19:04
IlyaIlya
335
asked Nov 13 '18 at 19:04
IlyaIlya
335
335
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
Your test data as shown at the top is not in the right form.
A list in OCaml has elements separated by semicolons (;). Your test data is using commas instead (,). Commas are used for tuples, which is why you're seeing a tuple in your result.
If you change , to ; in your test data you should see something closer to what you're looking for. There is at least one problem left to fix (in my testing).
answered Nov 13 '18 at 19:25
Jeffrey ScofieldJeffrey Scofield
47.4k24979
add a comment |
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1 Answer
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1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
Your test data as shown at the top is not in the right form.
A list in OCaml has elements separated by semicolons (;). Your test data is using commas instead (,). Commas are used for tuples, which is why you're seeing a tuple in your result.
If you change , to ; in your test data you should see something closer to what you're looking for. There is at least one problem left to fix (in my testing).
answered Nov 13 '18 at 19:25
Jeffrey ScofieldJeffrey Scofield
47.4k24979
add a comment |
Your test data as shown at the top is not in the right form.
A list in OCaml has elements separated by semicolons (;). Your test data is using commas instead (,). Commas are used for tuples, which is why you're seeing a tuple in your result.
If you change , to ; in your test data you should see something closer to what you're looking for. There is at least one problem left to fix (in my testing).
answered Nov 13 '18 at 19:25
Jeffrey ScofieldJeffrey Scofield
47.4k24979
add a comment |
Your test data as shown at the top is not in the right form.
A list in OCaml has elements separated by semicolons (;). Your test data is using commas instead (,). Commas are used for tuples, which is why you're seeing a tuple in your result.
If you change , to ; in your test data you should see something closer to what you're looking for. There is at least one problem left to fix (in my testing).
answered Nov 13 '18 at 19:25
Jeffrey ScofieldJeffrey Scofield
47.4k24979
Your test data as shown at the top is not in the right form.
A list in OCaml has elements separated by semicolons (;). Your test data is using commas instead (,). Commas are used for tuples, which is why you're seeing a tuple in your result.
If you change , to ; in your test data you should see something closer to what you're looking for. There is at least one problem left to fix (in my testing).
answered Nov 13 '18 at 19:25
Jeffrey ScofieldJeffrey Scofield
47.4k24979
answered Nov 13 '18 at 19:25
Jeffrey ScofieldJeffrey Scofield
47.4k24979
answered Nov 13 '18 at 19:25
Jeffrey ScofieldJeffrey Scofield
47.4k24979
answered Nov 13 '18 at 19:25
Jeffrey ScofieldJeffrey Scofield
47.4k24979
47.4k24979
add a comment |
add a comment |
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