fix solution for BigInt::min. Thanks, Derek!

diff --git a/solutions/src/bigint.rs b/solutions/src/bigint.rs
index 96958b47bbe3d262804dc78ac8ec59a0fab4a37d..5869ba89401076c8998bb7414dae31e71a3d738c 100644 (file)
--- a/solutions/src/bigint.rs
+++ b/solutions/src/bigint.rs
@@ -154,16 +154,14 @@ impl Minimum for BigInt {
             other
         } else {
             // compare back-to-front, i.e., most significant digit first
-            let mut idx = self.data.len()-1;
+            let mut idx = self.data.len();
             while idx > 0 {
+                idx = idx-1;
                 if self.data[idx] < other.data[idx] {
                     return self;
                 } else if self.data[idx] > other.data[idx] {
                     return other;
                 }
-                else {
-                    idx = idx-1;
-                }
             }
             // the two are equal
             return self;
@@ -285,7 +283,9 @@ mod tests {
         let b3 = BigInt::from_vec(vec![0, 1]);
 
         assert_eq!(b1.min(&b2), &b1);
+        assert_eq!(b2.min(&b1), &b1);
         assert_eq!(b3.min(&b2), &b2);
+        assert_eq!(b2.min(&b3), &b2);
     }
 
     #[test]