doasku

commit 581e11fbb24974750e8491d22fc8ae8dc2585c5b
parent 86c7bfdad89a06ef8cc35197d4c39d0a5ad42748
Author: Dimitrije Dobrota <mail@dimitrijedobrota.com>
Date:   Mon,  8 Apr 2024 20:48:45 +0200

Add check for pointing pairs and triplets

Diffstat:
M
main.cpp
 | 
70
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-

1 file changed, 69 insertions(+), 1 deletion(-)
diff --git a/main.cpp b/main.cpp
@@ -52,6 +52,44 @@ class Ref {
         res[field] = value + 1;
     }
 
+    auto get_pointing() const {
+        std::array<std::vector<std::tuple<uint8_t, uint8_t>>, 2> res;
+
+        for (uint8_t i = 0; i < 9; i++) {
+            const uint8_t popcnt = std::popcount(ref[i]);
+            if (popcnt < 2 || popcnt > 3) continue;
+
+            uint16_t row_mask = 0x7;
+            uint16_t col_mask = 0x49;
+
+            if ((seen_point_row & (1 << i)) == 0) {
+                for (uint8_t k = 0; k < 3; k++) {
+                    if (std::popcount(uint16_t(row_mask & ref[i])) == popcnt) {
+                        seen_point_row |= 1 << i;
+                        res[0].emplace_back(k, i);
+                        break;
+                    }
+
+                    row_mask <<= 3;
+                }
+            }
+
+            if ((seen_point_col & (1 << i)) == 0) {
+                for (uint8_t k = 0; k < 3; k++) {
+                    if (std::popcount(uint16_t(col_mask & ref[i])) == popcnt) {
+                        seen_point_col |= 1 << i;
+                        res[1].emplace_back(k, i);
+                        break;
+                    }
+
+                    col_mask <<= 3;
+                }
+            }
+        }
+
+        return res;
+    }
+
     auto get_hidden_singles() const {
         std::vector<std::tuple<uint8_t, uint8_t>> res;
 
@@ -318,6 +356,9 @@ class Ref {
     mutable uint16_t seen_naked_pair = 0;
     mutable uint16_t seen_naked_triplet = 0;
     mutable uint16_t seen_naked_quad = 0;
+
+    mutable uint16_t seen_point_row = 0;
+    mutable uint16_t seen_point_col = 0;
 };
 
 class Grid {
@@ -440,6 +481,33 @@ class Grid {
 
                     changes++;
                 }
+
+                const auto pt = subgrids[subgrid].get_pointing();
+                for (const auto [row, val] : pt[0]) {
+                    static uint8_t mapping[9][2] = {{1, 2}, {0, 2}, {0, 1}, {4, 5}, {3, 5},
+                                                    {3, 4}, {7, 8}, {6, 8}, {6, 7}};
+
+                    std::cout << "pointing row: " << (int)subgrid << " " << (int)row << " " << (int)val
+                              << std::endl;
+
+                    _clear_row(mapping[subgrid][0], row, val);
+                    _clear_row(mapping[subgrid][1], row, val);
+
+                    changes++;
+                }
+
+                for (const auto [col, val] : pt[1]) {
+                    static uint8_t mapping[9][2] = {{3, 6}, {4, 7}, {5, 8}, {0, 6}, {1, 7},
+                                                    {2, 8}, {0, 3}, {1, 4}, {2, 5}};
+
+                    std::cout << "pointing col: " << (int)subgrid << " " << (int)col << " " << (int)val
+                              << std::endl;
+
+                    _clear_col(mapping[subgrid][0], col, val);
+                    _clear_col(mapping[subgrid][1], col, val);
+
+                    changes++;
+                }
             }
 
             for (uint8_t row = 0; row < 9; row++) {
@@ -716,7 +784,7 @@ class Grid {
 
     bool _is_finished(uint8_t subgrid) {
         for (uint8_t i = 0; i < 9; i++) {
-            if (subgrids[subgrid].get_ref(i)) return false;
+            if (!subgrids[subgrid].get_value(i)) return false;
         }
         return true;
     }