Initial commit

838/838-1.cpp

@@ -0,0 +1,74 @@
+#include <string>
+#include <iostream>
+#include <set>
+
+namespace {
+
+enum Dominoes : char {
+    Dot = '.',
+    L = 'L',
+    R = 'R',
+};
+
+class Solution {
+    public:
+        std::string pushDominoes(std::string dominoes) {
+            bool has_actions = true;
+            
+            while (has_actions) {
+                size_t processed_dot = -1;
+                size_t actions_found = 0;
+                for (size_t i = 0; i < dominoes.size(); ++i) {
+                    char d = dominoes[i];
+                    if ((d == L || d == R) && processed_dot != i) {
+                        ++actions_found;
+
+                        bool left_dot = false;
+                        bool right_dot = false;
+
+                        if (i > 0 && (dominoes[i - 1] == Dot && processed_dot != (i - 1)))
+                            left_dot = true;
+
+                        if (i < (dominoes.size() - 1) && dominoes[i + 1] == Dot)
+                            right_dot = true;
+
+                        if (d == L && left_dot) {
+                            if (i > 1 && dominoes[i - 2] == R && processed_dot != (i - 2))
+                                --actions_found;
+                            else {
+                                dominoes[i - 1] = L;
+                                processed_dot = (i - 1);
+                            }
+                        }
+
+                        else if (d == R && right_dot) {
+                            if (i < (dominoes.size() - 2) && dominoes[i + 2] == L)
+                                --actions_found;
+                            else {
+                                dominoes[i + 1] = R;
+                                processed_dot = (i + 1);
+                            }
+                        }
+
+                        else
+                            --actions_found;
+                    }
+                }
+                if (!actions_found)
+                    has_actions = false;
+                
+                std::cout << "step   " << dominoes << '\n';
+            }
+            return dominoes;
+        }
+    };
+}
+
+#include <gtest/gtest.h>
+
+TEST(P838_1, 1) {
+    std::string input = ".L.R...LR..L..";
+    Solution s;
+    auto result = s.pushDominoes(input);
+    EXPECT_EQ(result, std::string("LL.RR.LLRRLL.."));
+}