From b210cb5b323a22849361cb2e2fa7dd3f71e8b881 Mon Sep 17 00:00:00 2001
From: Yuri Tatishchev <itatishch@gmail.com>
Date: Mon, 9 Feb 2026 12:14:20 -0800
Subject: [PATCH] lab04: init

---
 lab04/mapFilter.hs | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)
 create mode 100644 lab04/mapFilter.hs

diff --git a/lab04/mapFilter.hs b/lab04/mapFilter.hs
new file mode 100644
index 0000000..f381325
--- /dev/null
+++ b/lab04/mapFilter.hs
@@ -0,0 +1,25 @@
+-- USING MAP, convert a list of Strings to a list of Integers.
+stringsToNums :: [String] -> [Integer]
+
+
+-- USING MAP, take a list of integers and return a list with
+-- the equivalent absolute values.
+
+
+-- USING ZIPWITH, concatenate a list of first names with
+-- a list of last names to produce a list of full names.
+
+
+-- USING MAP AND FILTER, square all positive numbers in a list;
+-- strip out 0 and negative numbers.
+
+
+main :: IO ()
+main = do
+  print $ stringsToNums []
+  print $ stringsToNums ["1", "2", "3", "4", "5"]
+  print $ mapAbsVal [-4, 3, 2, -99, 54]
+  print $ mapAbsVal $ stringsToNums ["-4", "7", "-22"]
+  print $ fullNames ["John", "Wes Happen", "Holly"] ["Smith", "Ng", "Wood"]
+  print $ squarePostives [2, -3, 45, 5, 0, 7, -6]
+  
\ No newline at end of file