new files

Task/Bulls-and-cows/PHP/bulls-and-cows.php

@@ -0,0 +1,40 @@
+<?php
+$size = 4;
+
+$chosen = implode(array_rand(array_flip(range(1,9)), $size));
+
+echo "I've chosen a number from $size unique digits from 1 to 9; you need
+to input $size unique digits to guess my number\n";
+
+for ($guesses = 1; ; $guesses++) {
+    while (true) {
+        echo "\nNext guess [$guesses]: ";
+        $guess = rtrim(fgets(STDIN));
+        if (!checkguess($guess))
+            echo "$size digits, no repetition, no 0... retry\n";
+        else
+            break;
+    }
+    if ($guess == $chosen) {
+        echo "You did it in $guesses attempts!\n";
+        break;
+    } else {
+        $bulls = 0;
+        $cows = 0;
+        foreach (range(0, $size-1) as $i) {
+            if ($guess[$i] == $chosen[$i])
+                $bulls++;
+            else if (strpos($chosen, $guess[$i]) !== FALSE)
+                $cows++;
+        }
+        echo "$cows cows, $bulls bulls\n";
+    }
+}
+
+function checkguess($g)
+{
+  global $size;
+  return count(array_unique(str_split($g))) == $size &&
+    preg_match("/^[1-9]{{$size}}$/", $g);
+}
+?>