php基础算法(国外英语资料).docVIP

php基础算法(国外英语资料) For the 1. year of the ox: a cattle cow, 4 years old can give birth, every year a student, which is the same as the cow, To 15 years old sterilization, no longer born, 20 years old died, asked how many cows after n years? Function niuFunc ($n) { Static $num = 1; /*/ For ($j = 1; $j $n; $j++) { If ($j = 4 $j 15) { $num++; NiuFunc ($n-$j); } If ($j = 20) { $num--; } } } 2. merging multiple arrays without using array_merge () Function, t () { $c = func_num_args () -1; $a = func_get_args (); For ($i=0; $i=$c; $i++) { If (is_array ($a[$i])) { For ($j=0; $jcount ($a[$i]); $j++) { $r[] = $a[$i][$j]; } } Else { Die (Not, a, array,...); } } Return $r; } 3. find the elements you want in an array (two - point lookup algorithm). Train of thought: take a value in the array as the boundary, and then recursively search until the end Function, find ($array, $low, $high, $k) { If ($low $high) { $mid = intval (($low+$high) /2); If ($array[$mid] = $k) { Return $mid; } Elseif ($k $array[$mid]) { Return, find ($array, $low, $mid-1, $k); } Else { Return, find ($array, $mid+1, $high, $k); } } Die (Not, have,...); } 4. quick sort Function Q ($arr) { If (count ($arr) 1) { Return $arr; } $key = $arr[0]; $l = array (); $r = array (); For ($i=0; $icount ($arr); $i++) { If ($arr[$i] $key) { $l[] = $arr[$i]; } Else { $r[] = $arr[$i]; } } $l = q ($l); $r = q ($r); Return, array_merge ($l, $key, $r); } 5. in a set of numbers, insert a number, insert it in its original order, and maintain the original sort. Train of thought: find the position that is larger than the number to insert, replace, and then shift the number behind Function in ($arr, $in) { If ($arr[$n-1] $in) { $arr[$n+1] = $in; Print_r ($arr); } For ($i=0; $i$n; $i++) { If ($arr[$i] = $in) { $t1= $arr[$i]; $arr[$i] = $in; } The following data / / A For ($j=$i+1; $j$n+1; $j++) { $t2 = $arr[$j]; $arr[$j] = $t1; $t1 = $t2; } } } 6, the first to draw a diamond play, many people learn C when the book has been painte