1 files changed, 12 insertions, 0 deletions
diff --git a/progs/test.py b/progs/test.py
new file mode 100644
index 0000000..f168c9b
--- /dev/null
+++ b/progs/test.py
@@ -0,0 +1,12 @@
+def find_first_duplicate(nums):
+    num_set = set()
+    no_duplicate = -1
+
+    for i in range(len(nums)):
+
+        if nums[i] in num_set:
+            return nums[i]
+        else:
+            num_set.add(nums[i])
+
+    return no_duplicate
+\ No newline at end of file