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diff --git a/Homework/cs4700/dart/streams.dart b/Homework/cs4700/dart/streams.dart
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+++ b/Homework/cs4700/dart/streams.dart
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+import 'dart:io';
+
+// Generates a stream of n fibonacci numbers, sleeping 1 second every iteration
+Stream<int> Function() fibonnaciNumbers(int n) {
+  final Stream<int> Function() func = (() async* {
+    var x = 0, y = 1;
+    for (int i = 0; i <= n; i++) {
+      yield x;
+      sleep(new Duration(seconds: 1));
+      y += x;
+      x = y - x;
+    }
+  });
+  return func;
+}
+
+// Filters a stream of integers with a function predicate determining to each of the elements in the stream.
+Stream<int> Function() streamFilter(Stream<int> stream, bool Function(int) f) {
+  final Stream<int> Function() func = (() async* {
+    await for (var i in stream) {
+      if (f(i)) {
+        yield i;
+      }
+    }
+  });
+  return func;
+}
+
+// Iterates over a stream, accumulatively applying a binary function to a stream of integers until the last
+// element and returns the accumulation.
+Stream<int> Function() streamAccumulation(
+    Stream<int> stream, int Function(int, int) f, initial) {
+  final Stream<int> Function() func = (() async* {
+    int a = initial;
+    await for (var i in stream) {
+      a = f(a, i);
+      yield a;
+    }
+  });
+  return func;
+}
+
+Stream<int> Function() generateNumbers(int n) {
+  final Stream<int> Function() func = (() async* {
+    for (int i = 1; i <= n; i++) {
+      await Future<void>.delayed(const Duration(seconds: 1));
+      yield i;
+    }
+  });
+  return func;
+}
+
+// Given a list of lists, returns a list containing all the non-null elements of each list into a single list
+List? flatten(List<List?>? aList) {
+  if (aList == null) return null;
+  return aList
+      .where((i) => i != null)
+      .expand((i) => i!)
+      .where((i) => i != null)
+      .toList();
+}
+
+// Generates a nested list where each element's index i is in a sublist of depth i+1.
+// For example, deepen([1,2,3]) => [1, [2, [3]]]
+List? deepen(List? aList) {
+  if (aList == null) return null;
+  return aList.reversed
+      .fold([], (a, x) => (a != null && a.isEmpty) ? [x] : [x, a]);
+}
+
+void main(List<String> arguments) async {
+  print('flattening [[0,1], [2]] yields ${flatten([
+        [0, 1],
+        [2]
+      ])}');
+  print('flattening [[0,1], [2], null] yields ${flatten([
+        [0, 1],
+        [2],
+        null
+      ])}');
+  print('flattening [[0,1, null], [2]] yields ${flatten([
+        [0, 1, null],
+        [2]
+      ])}');
+  print('flattening null yields ${flatten(null)}');
+  print('flattening [null] yields ${flatten([null])}');
+  print('deepening [0,1,2] yields ${deepen([0, 1, 2])}');
+  print('deepening [0,null,2] yields ${deepen([0, null, 2])}');
+  print('deepening [0] yields ${deepen([0])}');
+  print('deepening [] yields ${deepen([])}');
+  print('deepening null yields ${deepen(null)}');
+  await for (final number in fibonnaciNumbers(7)()) {
+    print('fibonnaci number is ${number}');
+  }
+  await for (final number in streamFilter(generateNumbers(10)(), ((a) {
+    return a % 2 == 0;
+  }))()) {
+    print('filtered number is $number');
+  }
+
+  await for (final number in streamAccumulation(generateNumbers(10)(), ((a, b) {
+    return a + b;
+  }), 0)()) {
+    print('cumulative number is $number.');
+  }
+}