update repo

Author: Allui

Readme.md

@@ -1,2 +1,7 @@
-# МОАИС 154м
-### Морозов Иван
+# МОАИС 154м
+### Морозов Иван
+
+first - первое задание
+first_if - задание на if.. case..
+min - reduce и filter
+db - мини база данных на списках

db.erl

@@ -0,0 +1,28 @@
+-module(db).
+-export([new/0, put/3, delete/2,find/2,get/2]).
+
+
+%db:new()
+%db:put(K,V,DB)
+%db:delete(K,DB)
+%db:get(K,DB)
+%db:find(V,DB)
+
+%Db = db:new().
+%Db1 = db:put(k1,v1,Db).
+
+new()->[].
+
+put(K,V,[]) -> [{K,V}];
+put(K,V,Db) -> [{K,V}|delete(K,Db)].
+
+delete(K,Db) -> [{K1,V1}||{K1,V1} <- Db, K=/=K1].
+
+get(K,Db) -> getValue([{K1,V1}||{K1,V1} <- Db, K==K1]).
+
+getValue([]) -> {error, not_exists};
+getValue([{_,V}|_])->V.
+
+find(V,Db) -> findeResult([{K1,V1}||{K1,V1} <- Db, V==V1]).
+findeResult([]) -> {error, not_finde};
+findeResult(L) -> [K1||{K1,_} <- L].

first_if.erl

@@ -0,0 +1,42 @@
+-module(first_if).
+-export([hi/0, fact/1, fib/1, member/2, cost/1]).
+
+hi() ->
+	io:format("Hello!").
+
+fact(N) -> 
+    if 
+        N == 0 -> 1;
+        true -> N*fact(N-1)
+    end.
+
+fib(N) -> 
+    if 
+        N == 0 -> 0;
+        N == 1 -> 1;
+        true -> fib(N-1)+fib(N-2)
+    end.
+
+member(S,E) ->
+    case S of 
+        [] -> false;
+        [H|_] when H == E -> true;
+        [_|T] -> member(T,E)
+    end.
+
+price(Item) -> 
+    case Item of 
+        apple -> 100;
+        pear -> 150;
+        milk -> 70;
+        beef -> 400;
+        pork -> 300
+    end.
+
+%[{apple, count}, ...]
+%cost(L)-> get summ
+cost(L) ->
+    case L of 
+        [] -> 0;
+        [{S,C}|T] -> price(S)*C+cost(T)
+    end.

min.erl

@@ -0,0 +1,8 @@
+-module(min).
+-export([reduce/3,filter/2]).
+
+reduce(_, Start, []) -> Start;
+reduce(F, Start,[H|T]) -> reduce(F,F(H,Start),T).
+    
+filter(_,[])->[];
+filter(P,L) -> [X || X <- L, P(X)].