diff --git a/220-contains-duplicate-3.go b/220-contains-duplicate-3.go
new file mode 100644
index 0000000..a471a09
--- /dev/null
+++ b/220-contains-duplicate-3.go
@@ -0,0 +1,22 @@
+package main
+
+import "math"
+
+func ContainsNearbyAlmostDuplicate(nums []int, k int, t int) bool {
+	if k < 1 {
+		return false
+	}
+
+	for wSz := 1; wSz <= k; wSz++ {
+		ws := 0
+		for we := ws + wSz; we < len(nums); we++ {
+			if int(math.Abs(float64(nums[ws]-nums[we]))) <= t {
+				return true
+			}
+			ws++
+		}
+
+	}
+
+	return false
+}
diff --git a/220-contains-duplicate-3_test.go b/220-contains-duplicate-3_test.go
new file mode 100644
index 0000000..54eb96b
--- /dev/null
+++ b/220-contains-duplicate-3_test.go
@@ -0,0 +1,12 @@
+package main
+
+import (
+	"github.com/stretchr/testify/assert"
+	"testing"
+)
+
+func TestContainsNearbyAlmostDuplicate(t *testing.T) {
+	assert.False(t, ContainsNearbyAlmostDuplicate([]int{1, 5, 9, 1, 5, 9}, 2, 3))
+	assert.True(t, ContainsNearbyAlmostDuplicate([]int{1, 2, 3, 1}, 3, 0))
+	assert.True(t, ContainsNearbyAlmostDuplicate([]int{1, 0, 1, 1}, 1, 2))
+}