1 files changed, 48 insertions, 0 deletions
diff --git a/11/src/stuff.rs b/11/src/stuff.rs
new file mode 100644
index 0000000..82540ef
--- /dev/null
+++ b/11/src/stuff.rs
@@ -0,0 +1,48 @@
+use core::cmp::{max, min};
+use std::io::{BufRead};
+
+pub fn read_helper<'a, 'b, R: BufRead>(r: &'a mut R, buf: &'b mut Vec<u8>, token: u8) -> std::io::Result<usize> {
+    buf.clear();
+    let num_bytes = r.read_until(token, buf)?;
+    if buf.last() == Some(& token) { buf.pop(); }
+    Ok(num_bytes)
+}
+
+pub fn is_galaxy(c: u8) -> bool {
+    c == b'#'
+}
+
+pub type Position = [usize; 2];
+
+pub fn cumulative_sum_expansion(doubling: & [bool], factor: usize) -> Vec<usize> {
+    let mut ret: Vec<usize> = Vec::with_capacity(doubling.len());
+
+    let mut sum: usize = 0;
+    for &x in doubling.into_iter() {
+        if x {
+            sum += factor;
+        }
+        else {
+            sum += 1;
+        }
+        ret.push(sum);
+    }
+    
+    ret
+}
+
+pub fn distance(cumul_rows: & [usize], cumul_cols: & [usize], p: & Position, q: & Position) -> usize {
+    (cumul_rows[max(p[0], q[0])] - cumul_rows[min(p[0], q[0])])
+        + (cumul_cols[max(p[1], q[1])] - cumul_cols[min(p[1], q[1])])
+}
+
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test() {
+    }
+
+}