Merge pull request #347 from SHQHDMR/master

php实现矩阵乘法

php/38_divide_and_conquer/matrix_production.php

@@ -0,0 +1,77 @@
+<?php
+
+function popRow(&$matrix)
+{
+    return empty($matrix) ? [] : [array_shift($matrix)];
+}
+
+function popColumn(&$matrix)
+{
+    $column = [];
+
+    foreach ($matrix as $key => &$row) {
+        $data = array_shift($row);
+        if (empty($data) || empty($row)) {
+            unset($matrix[$key]);
+        }
+        $column[] = [$data];
+    }
+    return $column;
+}
+
+function countProduction($row, $column)
+{
+    for ($i = 0, $sum = 0; $i < count($row[0]); $i++) {
+        $sum += $row[0][$i] * $column[$i][0];
+    }
+    return $sum;
+}
+
+function merger($value1, $value2, $value3, $value4)
+{
+    if (empty($value2) && empty($value3)) {
+        return $value1;
+    } else {
+        $array12 = array_merge([$value1], !is_array($value2) ? [$value2] : $value2);
+        if (!is_array($value3)) {
+            $array34 = array_merge([$value3], !is_array($value4) ? [$value4] : $value4);
+            return [$array12, $array34];
+        } else {
+            for ($i = 0, $array34 = []; $i < count($value3); $i++) {
+                $array34[] = array_merge($value3[$i], $value4[$i]);
+            }
+            return array_merge([$array12], $array34);
+        }
+    }
+}
+
+function matrixProduction($matrix1, $matrix2)
+{
+    $row = popRow($matrix1);
+    $column = popColumn($matrix2);
+
+    if (empty($row) || empty($column)) {
+        return [];
+    }
+
+    $value1 = countProduction($row, $column);
+    $value2 = matrixProduction($row, $matrix2);
+    $value3 = matrixProduction($matrix1, $column);
+    $value4 = matrixProduction($matrix1, $matrix2);
+
+    return merger($value1, $value2, $value3, $value4);
+}
+
+$matrix1 = [
+    [1, 2, 3],
+    [4, 5, 6],
+    [7, 8, 9],
+];
+
+$matrix2 = [
+    [1, 2, 3],
+    [4, 5, 6],
+    [7, 8, 9],
+];
+
+var_dump(matrixProduction($matrix1, $matrix2));