PHP实现合并两个有序数组的方法分析

$arr1 = array(1,2,3,4,5,6,7,8);$arr2 = array(3,4,5,7,9,10);//方法1function mergeOrderly1($arr1,$arr2){ $i=0;$j=0; $int = array(); while($i<count($arr1) && $j<count($arr2)){  $int[] = $arr1[$i]<$arr2[$j]?$arr1[$i++]:$arr2[$j++]; } while($i<count($arr1)){  $int[] = $arr1[$i++]; } while($j<count($arr2)){  $int[] = $arr2[$j++]; } //$int = array_merge($int,array_slice($arr1,$i)); //$int = array_merge($int,array_slice($arr2,$j)); return $int;}//方法2function mergeOrderly2($arr1,$arr2){ $arr = array();//定义最终数组容器 $arr2Num = count($arr2);//统计数组长度 $arr1Num = count($arr1); $i1 = 0;//数组1 的循环标记 $i2 = 0;//数组2 的循环标记 while($i1 < $arr1Num || $i2 < $arr2Num){//是否还需要合并  if($i1 < $arr1Num && $i2 < $arr2Num){//当两个数组都没有到达末尾，情况一   if($arr1[$i1] > $arr2[$i2]){//需要比较数组1和数组2，小的放入目标数组，并且标记+1    $arr[] = $arr2[$i2];    $i2++;   }else{    $arr[] = $arr1[$i1];    $i1++;   }  }elseif($i1 < $arr1Num && $i2 >= $arr2Num){//数组2 已经到达末尾，而数组1还为到达，情况二   $arr[] = $arr1[$i1];//直接把数组1的内容插入到目标数组中   $i1++;  }elseif($i2 < $arr2Num && $i1 >= $arr1Num){//数组1已经到达末尾，而数组2还未到达，情况三   $arr[] = $arr2[$i2];//直接把数组2的内容插入到目标数组中   $i2++;  } } return $arr;}print_r(mergeOrderly1($arr1,$arr2));print_r(mergeOrderly2($arr1,$arr2));

Array( [0] => 1 [1] => 2 [2] => 3 [3] => 3 [4] => 4 [5] => 4 [6] => 5 [7] => 5 [8] => 6 [9] => 7 [10] => 7 [11] => 8 [12] => 9 [13] => 10)Array( [0] => 1 [1] => 2 [2] => 3 [3] => 3 [4] => 4 [5] => 4 [6] => 5 [7] => 5 [8] => 6 [9] => 7 [10] => 7 [11] => 8 [12] => 9 [13] => 10)

$arr1 = array(1,2,3,4,5);$arr2 = array(1,2,3,6,7);$arr3 = array('0'=>1,'1'=>2,'2'=>3,'3'=>4,'4'=>5);$arr4 = array('0'=>1,'1'=>2,'2'=>3,'3'=>6,'4'=>7);$arr5 = array('0'=>1,'a'=>2,'b'=>3,'c'=>4,'4'=>5);$arr6 = array('0'=>1,'a'=>2,'c'=>3,'d'=>6,'4'=>7);var_dump(array_merge($arr1, $arr2));var_dump($arr1+$arr2);var_dump(array_keys(array_flip($arr1)+array_flip($arr2)));echo '<br>';var_dump(array_merge($arr3, $arr4));var_dump($arr3+$arr4);var_dump(array_keys(array_flip($arr3)+array_flip($arr4)));echo '<br>';var_dump(array_merge($arr5, $arr6));var_dump($arr5+$arr6);

array(10) { [0]=> int(1) [1]=> int(2) [2]=> int(3) [3]=> int(4) [4]=> int(5) [5]=> int(1) [6]=> int(2) [7]=> int(3) [8]=> int(6) [9]=> int(7) } array(5) { [0]=> int(1) [1]=> int(2) [2]=> int(3) [3]=> int(4) [4]=> int(5) } array(7) { [0]=> int(1) [1]=> int(2) [2]=> int(3) [3]=> int(4) [4]=> int(5) [5]=> int(6) [6]=> int(7) } array(10) { [0]=> int(1) [1]=> int(2) [2]=> int(3) [3]=> int(4) [4]=> int(5) [5]=> int(1) [6]=> int(2) [7]=> int(3) [8]=> int(6) [9]=> int(7) } array(5) { [0]=> int(1) [1]=> int(2) [2]=> int(3) [3]=> int(4) [4]=> int(5) } array(7) { [0]=> int(1) [1]=> int(2) [2]=> int(3) [3]=> int(4) [4]=> int(5) [5]=> int(6) [6]=> int(7) } array(8) { [0]=> int(1) ["a"]=> int(2) ["b"]=> int(3) ["c"]=> int(3) [1]=> int(5) [2]=> int(1) ["d"]=> int(6) [3]=> int(7) } array(6) { [0]=> int(1) ["a"]=> int(2) ["b"]=> int(3) ["c"]=> int(4) [4]=> int(5) ["d"]=> int(6) }