diff --git a/2023/day5/example-input.txt b/2023/day5/example-input.txt
new file mode 100644
index 0000000..bd902a4
--- /dev/null
+++ b/2023/day5/example-input.txt
@@ -0,0 +1,33 @@
+seeds: 79 14 55 13
+
+seed-to-soil map:
+50 98 2
+52 50 48
+
+soil-to-fertilizer map:
+0 15 37
+37 52 2
+39 0 15
+
+fertilizer-to-water map:
+49 53 8
+0 11 42
+42 0 7
+57 7 4
+
+water-to-light map:
+88 18 7
+18 25 70
+
+light-to-temperature map:
+45 77 23
+81 45 19
+68 64 13
+
+temperature-to-humidity map:
+0 69 1
+1 0 69
+
+humidity-to-location map:
+60 56 37
+56 93 4
\ No newline at end of file
diff --git a/2023/day5/src/main.rs b/2023/day5/src/main.rs
index e7a11a9..43148d4 100644
--- a/2023/day5/src/main.rs
+++ b/2023/day5/src/main.rs
@@ -1,3 +1,82 @@
+use std::ops::Range;
+use std::collections::HashMap;
+const FILE_STR: &'static str = include_str!("input.txt");
+
+#[derive(Debug)]
+enum DataType {
+    Seeds,
+    Soil,
+    Fertilizer,
+    Water,
+    Light,
+    Temperature,
+    Humidity,
+    Location,
+}
+
+#[derive(Debug, Default)]
+struct DataMap {
+    from_range: Range<u64>,
+    to_range: Range<u64>,
+}
+
+impl DataMap {
+    fn new(from_start: u64, to_start: u64, map_length: u64) -> Self {
+        let to_range = to_start..to_start + map_length;
+        let from_range = from_start..from_start + map_length;
+
+        DataMap {
+            from_range,
+            to_range
+        }
+    }
+
+    fn get_dest_idx(&self, src_value: u64) -> u64 {
+        let src_index = src_value.checked_sub(self.to_range.start);
+        let dest_index = if let Some(idx) = src_index {
+            self.from_range.start.checked_add(idx)
+        } else {
+            Some(src_value)
+        };
+
+        match dest_index {
+            Some(n) => n,
+            None => src_value
+        }
+    }
+
+    fn get_src_idx(&self, dest_value: u64) -> u64 {
+        let dest_index = dest_value.checked_sub(self.from_range.start);
+        let src_index = if let Some(idx) = dest_index {
+            self.to_range.start.checked_add(idx)
+        } else {
+            Some(dest_value)
+        };
+
+        match src_index {
+            Some(n) => n,
+            None => dest_value
+        }
+    }
+}
+
+#[derive(Debug, Default)]
+struct Almanac {
+    seeds: Vec<u64>,
+    maps: HashMap<(DataType, DataType), Vec<DataMap>>,
+}
+
+impl Almanac {
+    fn parse(input: &str) -> Self {
+        todo!();
+    }
+}
+
 fn main() {
     println!("Hello, world!");
 }
+
+#[cfg(test)]
+mod tests {
+    const EXAMPLE_FILE_STR: &'static str = include_str!("example-input.txt");
+}
\ No newline at end of file