From fdba35e4acde8eb11ffd67812b2db857b470b23e Mon Sep 17 00:00:00 2001
From: Nilstrieb <48135649+Nilstrieb@users.noreply.github.com>
Date: Sun, 23 Jan 2022 20:44:57 +0100
Subject: [PATCH] dfs and bfs

---
 .gitignore |  3 ++
 Cargo.toml |  8 ++++++
 src/lib.rs | 81 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 92 insertions(+)
 create mode 100644 .gitignore
 create mode 100644 Cargo.toml
 create mode 100644 src/lib.rs

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..408b8a5
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+/target
+Cargo.lock
+.idea
\ No newline at end of file
diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..06f5afd
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,8 @@
+[package]
+name = "game_trees"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..32d1738
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,81 @@
+#![allow(dead_code)]
+
+pub struct Node<T> {
+    value: T,
+    children: Vec<Node<T>>,
+}
+
+#[macro_export]
+macro_rules! tree {
+    ($first:expr $(, $($rest:expr),*)?) => {
+        $crate::Node {
+            value: $first,
+            children: vec![$($($rest),*)?],
+        }
+    };
+}
+
+mod search {
+    use crate::Node;
+    use std::collections::VecDeque;
+
+    pub fn breadth_first_search<T: Eq>(tree: &Node<T>, searched: &T) -> bool {
+        let mut candidates = VecDeque::new();
+        candidates.push_back(tree);
+
+        loop {
+            if let Some(candidate) = candidates.pop_front() {
+                if candidate.value == *searched {
+                    return true;
+                }
+
+                candidates.extend(candidate.children.iter());
+            } else {
+                break;
+            }
+        }
+
+        false
+    }
+
+    pub fn depth_first_search<T: Eq>(tree: &Node<T>, searched: &T) -> bool {
+        if tree.value == *searched {
+            return true;
+        }
+
+        for child in &tree.children {
+            if depth_first_search(&child, searched) {
+                return true;
+            }
+        }
+
+        false
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::search;
+
+    #[test]
+    fn dfs() {
+        let tree = tree!(1, tree!(6, tree!(5), tree!(4)), tree!(6));
+
+        let has_seven = search::depth_first_search(&tree, &7);
+        let has_five = search::depth_first_search(&tree, &5);
+
+        assert!(!has_seven);
+        assert!(has_five);
+    }
+
+    #[test]
+    fn bfs() {
+        let tree = tree!(1, tree!(6, tree!(5), tree!(4)), tree!(6));
+
+        let has_seven = search::breadth_first_search(&tree, &7);
+        let has_five = search::breadth_first_search(&tree, &5);
+
+        assert!(!has_seven);
+        assert!(has_five);
+    }
+}