diff --git "a/leetcode3/\353\202\250\355\232\250\354\240\225/121. Best Time to Buy and Sell Stock.py" "b/leetcode3/\353\202\250\355\232\250\354\240\225/121. Best Time to Buy and Sell Stock.py"
new file mode 100644
index 00000000..8e92a585
--- /dev/null
+++ "b/leetcode3/\353\202\250\355\232\250\354\240\225/121. Best Time to Buy and Sell Stock.py"	
@@ -0,0 +1,13 @@
+class Solution:
+    def maxProfit(self, prices: List[int]) -> int:
+        ans = 0
+        small = prices[0]
+        
+        for i in range(len(prices)):
+            profit = prices[i] - small
+            ans = max(ans, profit)
+            small = min(small, prices[i])
+
+        return ans
+
+        
\ No newline at end of file