add in place deduplicate trick
diff --git a/SliceTricks.md b/SliceTricks.md
index f4c0c86..b04db7e 100644
--- a/SliceTricks.md
+++ b/SliceTricks.md
@@ -165,4 +165,22 @@
Yields the following:
```go
[[0 1 2] [3 4 5] [6 7 8] [9]]
+```
+
+### In-place deduplicate (comparable)
+
+```go
+import "sort"
+
+in := []int{3,2,1,4,3,2,1,4,1} // any item can be sorted
+sort.Ints(in)
+j := 0
+for i := 1; i < len(in); i++ {
+ if in[j] == in[i] {
+ continue
+ }
+ j++
+ in[i], in[j] = in[j], in[i]
+}
+fmt.Println(in[:j+1]) // [1 2 3 4]
```
\ No newline at end of file
