Merge two sorted arrays | Merge $arr1 [ 0. . $n1 - 1 ] and $arr2 [ 0. . $n2 - 1 ] into $arr3 [ 0. . $n1 + $n2 - 1 ] ; Traverse both array ; Check if current element of first array is smaller than current element of second array . If yes , store first array element and increment first array index . Otherwise do same with second array ; Store remaining elements of first array ; Store remaining elements of second array ; Driver code
< ? php function mergeArrays ( & $ arr1 , & $ arr2 , $ n1 , $ n2 , & $ arr3 ) { $ i = 0 ; $ j = 0 ; $ k = 0 ; while ( $ i < $ n1 && $ j < $ n2 ) { if ( $ arr1 [ $ i ] < $ arr2 [ $ j ] ) $ arr3 [ $ k ++ ] = $ arr1 [ $ i ++ ] ; else $ arr3 [ $ k ++ ] = $ arr2 [ $ j ++ ] ; } while ( $ i < $ n1 ) $ arr3 [ $ k ++ ] = $ arr1 [ $ i ++ ] ; while ( $ j < $ n2 ) $ arr3 [ $ k ++ ] = $ arr2 [ $ j ++ ] ; } $ arr1 = array ( 1 , 3 , 5 , 7 ) ; $ n1 = sizeof ( $ arr1 ) ; $ arr2 = array ( 2 , 4 , 6 , 8 ) ; $ n2 = sizeof ( $ arr2 ) ; $ arr3 [ $ n1 + $ n2 ] = array ( ) ; mergeArrays ( $ arr1 , $ arr2 , $ n1 , $ n2 , $ arr3 ) ; echo " Array ▁ after ▁ merging ▁ STRNEWLINE " ; for ( $ i = 0 ; $ i < $ n1 + $ n2 ; $ i ++ ) echo $ arr3 [ $ i ] . " ▁ " ; ? >