hackerrank-php

Practice > Algorithms > Warmup

function solveMeFirst($a,$b){
	return $a + $b;
}

function simpleArraySum($ar) {
 $sum = 0;
 foreach($ar as $value){
 $sum+=$value;
 }
 return $sum;
}

function compareTriplets($a, $b) {
 $length = count($a);
 $aliceScore = 0;
 $bobScore = 0;
 for($i=0; $i<$length; $i++){
 if($a[$i] == $b[$i]){
 continue;
 }
 if($a[$i] > $b[$i]){
 $aliceScore++;
 continue;
 }
 $bobScore++;
 }
 return [$aliceScore, $bobScore];
}

function aVeryBigSum($ar) {
 $sum = 0;
 foreach($ar as $value){
 $sum+=$value;
 }
 return $sum;
}

function diagonalDifference($arr) {
 $length = count($arr);
 $primaryDiagonal = 0;
 $secondaryDiagonal = 0;
 $lastIndex = $length - 1;
 for($i = 0; $i<$length; $i++){
 $primaryDiagonal+=$arr[$i][$i];
 $secondaryDiagonal+=$arr[$i][$lastIndex--];
 }
 return abs($primaryDiagonal - $secondaryDiagonal);
}

function plusMinus($arr) {
 $POSITIVES = 0;
 $NEGATIVES = 1;
 $ZEROES = 2;
 $length = count($arr);
 // declare the temp numbers to index positions
 $numbers = [0, 0, 0];
 // determine the plusMinus of the numbers
 foreach($arr as $val){
 if($val === 0){
 $numbers[$ZEROES] = $numbers[$ZEROES] + 1;
 continue;
 }
 if($val > 0){
 $numbers[$POSITIVES] = $numbers[$POSITIVES] + 1;
 continue;
 }
 $numbers[$NEGATIVES] = $numbers[$NEGATIVES] + 1;
 }
 $plusMinusArr = array_map(function ($number) use ($length) {
 return number_format($number/$length, 6);
 }, $numbers);
 foreach($plusMinusArr as $plusMinus){
 echo $plusMinus;
 echo "\n";
 }
}

function staircase($n) {
 $totalSteps = $n;
 $staircase = [];
 // start from the right steps
 for($n; $n>0; $n--){
 $stairs = [];
 // proceed from left stair until the reach the final stair steps
 // then gradually increase the starting stair
 for($i=1; $i<=$n; $i++){
 // if it reached the final step print the stairs "#" else the its spaces
 if($i == $n){
 // calculate the total stairs to print
 $totalPrintOfStairs = ($totalSteps - $n) + 1;
 for($totalPrintOfStairs; $totalPrintOfStairs>0; $totalPrintOfStairs--){
 array_push($stairs, "#");
 }
 array_push($staircase, $stairs);
 break;
 }
 array_push($stairs, "");
 }
 }
 // print the staircases
 foreach($staircase as $stairs){
 foreach($stairs as $stair){
 echo $stair;
 }
 echo "\n";
 }
}

function miniMaxSum($arr) {
 $maxSumTempArr = $arr;
 $minSumTempArr = $arr;
 // sort into ascending order and get the first four values
 sort($minSumTempArr);
 $minSumArr = array_splice($minSumTempArr, 0 ,4);
 // sort into descending order and get the first four values
 rsort($maxSumTempArr);
 $maxSumArr = array_splice($maxSumTempArr, 0, 4); 
 echo array_sum($minSumArr) . '' . array_sum($maxSumArr);
}

function birthdayCakeCandles($ar) {
 // count the recurring of the candle
 $candles = array_count_values($ar);
 // sort the recurring candle by descending & get the most recurring candle
 krsort($candles);
 $candlesBlowsValue = array_values($candles);
 return $candlesBlowsValue[0];
}

function timeConversion($s) {
 $strToTime = strtotime($s);
 return date('H:i:s', $strToTime);
}

function gradingStudents($grades) {
 $MODULO = 5;
 $finalGrades = [];
 $finalGrades = array_map(function($grade) use ($MODULO){
 // get the next multiplier by 5
 $nextMultiplier = $grade + ($MODULO - $grade % $MODULO);
 $difference = $nextMultiplier - $grade;
 // do not round up if grade less than 40 
 // the difference is 3 and greater than 3
 if($nextMultiplier < 40 || $difference === 3 || $difference > 3){
 return $grade;
 }
 
 // round up if the difference is less than 3
 return $nextMultiplier;
 }, $grades);
 return $finalGrades;
}