[최민지] Day19

leetcode3/최민지/284.py

@@ -0,0 +1,20 @@
+class PeekingIterator:
+    def __init__(self, iterator):
+        self.iterator = iterator
+        self.peek_value = iterator.next() if iterator.hasNext() else None
+
+    def peek(self):
+        return self.peek_value
+
+    def next(self):
+        current = self.peek_value
+
+        if self.iterator.hasNext():
+            self.peek_value = self.iterator.next()
+        else:
+            self.peek_value = None
+
+        return current
+
+    def hasNext(self):
+        return self.peek_value is not None