Add assignment 7

src/assignments/assignment07_grade.rs

@@ -0,0 +1,27 @@
+#[cfg(test)]
+mod test {
+    use super::super::assignment07::*;
+
+    #[test]
+    fn test_find() {
+        assert_eq!(
+            find("abc".as_bytes(), "abcdabcd".as_bytes()).collect::<Vec<usize>>(),
+            vec![0, 4]
+        );
+
+        assert_eq!(
+            find("aaba".as_bytes(), "aabaacaadaabaaba".as_bytes()).collect::<Vec<usize>>(),
+            vec![0, 9, 12]
+        );
+
+        assert_eq!(
+            find("ababac".as_bytes(), "abababcabababcabababc".as_bytes()).collect::<Vec<usize>>(),
+            vec![]
+        );
+
+        assert_eq!(
+            find("ababc".as_bytes(), "abc".as_bytes()).collect::<Vec<usize>>(),
+            vec![]
+        );
+    }
+}