diff --git a/cpp/0838-push-dominoes.cpp b/cpp/0838-push-dominoes.cpp
new file mode 100644
index 000000000..fa0ddb478
--- /dev/null
+++ b/cpp/0838-push-dominoes.cpp
@@ -0,0 +1,39 @@
+/*
+    Time: O(n)
+    Space: O(n)
+*/
+
+class Solution {
+public:
+    string pushDominoes(string dominoes) {
+        
+        string res = "";
+        char prev;
+        int n = dominoes.size(), count = 1;
+        
+        vector<int> left(n, 0), right(n, 0);
+        for (int i = 0; i < n; i++) {
+            if (dominoes[i] == 'R') { count = 1; prev = 'R'; }
+            else if (dominoes[i] != '.')    prev = dominoes[i];
+            if (prev == 'R' && dominoes[i] == '.')   right[i] = count++;
+        }
+        
+        prev = '.';
+        for (int i = n-1; i >= 0; i--) {
+            if (dominoes[i] == 'L') { count = 1; prev = 'L'; }
+            else if (dominoes[i] != '.')    prev = dominoes[i];
+            if (prev == 'L' && dominoes[i] == '.')   left[i] = count++;
+        }
+        
+        for (int i = 0; i < n; i++) {
+            if (!left[i] && !right[i]) res += dominoes[i];
+            else if (!left[i]) res += 'R';
+            else if (!right[i]) res += 'L';
+            else if (left[i] == right[i]) res += '.';
+            else if (left[i] < right[i]) res += 'L';
+            else res += 'R';
+        }
+        
+        return res;
+    }
+};