fix the code to pass the first three tests

hands_on/local_maxima_part2/local_maxima.py

@@ -7,4 +7,25 @@ def find_maxima(x):
     Output:
     idx -- list of indices of the local maxima in x
     """
-    return []
+    idx = []
+    # catch the case when input is an empty list
+    if x == []:
+        return idx
+    
+    # catch the case where a maximum is at the edge
+    if len(x) > 1:
+        if x[0] > x[1]:
+            idx.append(0)
+        if x[-1] > x[-2]:
+            idx.append(len(x)-1)
+
+    # if we only have two values, we are done
+    if len(x) == 2:
+        return idx
+
+    # other wise for everything not on the edge:
+    for i in range(1, len(x)-1):
+        if (x[i] > x[i-1]) & (x[i] > x[i+1]):
+            idx.append(i)
+    
+    return sorted(idx)