1 files changed, 80 insertions, 0 deletions
diff --git a/day01/src/main.rs b/day01/src/main.rs
new file mode 100644
index 0000000..f391c2e
--- /dev/null
+++ b/day01/src/main.rs
@@ -0,0 +1,80 @@
+use std::io;
+
+fn rotate(dial: i32, change: i32, all_zeros: &mut i32) -> i32 {
+    /*
+    let mut ret = dial + change;
+    if ret == 0 {
+        *all_zeros += 1;
+    }
+    while ret < 0 {
+        ret += 100;
+        if dial > 0 {
+            *all_zeros += 1;
+        }
+    }
+    while ret > 99 {
+        ret -= 100;
+        if dial > 0 {
+            *all_zeros += 1;
+        }
+    }
+    return ret;
+     */
+    let mut ret = dial;
+    let mut change = change;
+    loop {
+        if change < 0 {
+            ret -= 1;
+            change += 1;
+            if ret == -1 {
+                ret = 99;
+            }
+        } else {
+            ret += 1;
+            change -= 1;
+            if ret == 100 {
+                ret = 0;
+            }
+        }
+        if ret == 0 {
+            *all_zeros += 1;
+        }
+        if change == 0 {
+            break;
+        }
+    }
+    ret
+}
+
+fn main() {
+    let mut dial = 50;
+    let mut zeros = 0;
+    let mut all_zeros = 0;
+
+    loop {
+        let mut buffer = String::new();
+        let bytes = io::stdin().read_line(&mut buffer).unwrap();
+        if bytes == 0 {
+            break;
+        }
+        let (dir, value_str) = buffer.trim_end().split_at(1);
+        let left = match dir {
+            "L" => true,
+            "R" => false,
+            _ => panic!(),
+        };
+        let mut value = value_str.parse::<i32>().unwrap();
+        if left {
+            value = -value;
+        }
+        if value != 0 {
+            dial = rotate(dial, value, &mut all_zeros);
+        }
+        if dial == 0 {
+            zeros += 1;
+        }
+    }
+
+    println!("Zeros {}", zeros);
+    println!("All zeros {}", all_zeros);
+}