Update overlap.py

overlap.py

@@ -0,0 +1,39 @@
+### Utilities to get overlap between strings
+
+def get_overlap_length(left: str, right: str):
+    good_length, overlap = 0, ""
+    for i in range(min(len(left), len(right))):
+        if left[-i:] == right[:i]:
+            good_length = i
+            overlap = left[-i:]
+    return good_length, overlap
+
+def get_overlap_list(strings):
+    """
+    Returns a list of tuples of the form (overlap_length, overlap), one tuple for each pair of strings in the input list.
+    """
+    overlaps = []
+    for i in range(len(strings) - 1):
+        overlaps.append(get_overlap_length(strings[i], strings[i+1]))
+    return overlaps
+
+def unoverlap_list(strings):
+    """
+    Returns a list of tuples of the form (content, is_overlap), where is_overlap is a boolean indicating whether the content is an overlap or not.
+    """
+    overlaps = get_overlap_list(strings)
+    new_list = []
+    for index, string in enumerate(strings):
+        # Add the last overlap when needed
+        if index > 0 and len(overlaps[index-1][1]) > 0:
+            new_list.append((overlaps[index-1][1], True))
+
+        # prune the string with left and right overlaps
+        left_overlap_length, right_overlap_length = 0, 0
+        if index > 0:
+            left_overlap_length = overlaps[index-1][0]
+        if index < len(strings) - 1:
+            right_overlap_length = overlaps[index][0]
+
+        new_list.append((string[left_overlap_length:len(string)-right_overlap_length], False))
+    return new_list