PHP二分法
483 ワード
function binarySearch($a, $val) {
$low = 0;
$high = count($a) - 1;
while ($low <= $high) {
$mid = intval(($low + $high) / 2);
if ($a[$mid] == $val)
return $mid;
if ($a[$mid] > $val) {
$high = $mid - 1;
} else {
$low = $mid + 1;
}
}
return -1;
}
$a=array(1,2,3,4,5,8,69,100);
echo "you find de num is from left to right:".(binarySearch($a,8)+1);