Climbing the Leaderboard – Hackerrank Challenge – JavaScript Solution
This is the javascript solution for the Hackerrank problem – Climbing the Leaderboard – Hackerrank Challenge – JavaScript Solution.
Source – Ryan Fehr’s repository.
//Problem: https://www.hackerrank.com/challenges/climbing-the-leaderboard
//JavaScript
/*
Initial Thoughts:
We want to build a dense ranking map based on the scores as
we read them in
Using that and a pointer variables we can iterate 1 time
over the scores array, advancing an unknown number of steps
for each score that Alice has.
Time Complexity: O(n) //We only iterate over the scores and alice's scores once
Space Complexity: O(n) //We store the ranking map
*/
process.stdin.resume();
process.stdin.setEncoding('ascii');
var input_stdin = "";
var input_stdin_array = "";
var input_currentline = 0;
process.stdin.on('data', function (data) {
input_stdin += data;
});
process.stdin.on('end', function () {
input_stdin_array = input_stdin.split("\n");
main();
});
function readLine() {
return input_stdin_array[input_currentline++];
}
/////////////// ignore above this line ////////////////////
function main() {
var n = parseInt(readLine());
scores = readLine().split(' ');
scores = scores.map(Number);
var m = parseInt(readLine());
alice = readLine().split(' ');
alice = alice.map(Number);
let map = rankScores(scores),
index = scores.length - 1;
for (let score of alice) {
if (scores.length === 0) {
console.log("1");
} else {
for (let i = index; i >= 0; i--) {
index = i;
if (score < scores[i]) {
console.log(map.get(scores[i]) + 1);
break;
} else if (score === scores[i]) {
console.log(map.get(scores[i]));
break;
} else if (i === 0) {
console.log("1");
}
}
}
}
}
function rankScores (scores) {
let map = new Map(),
rank = 1;
for (let leaderScore of scores) {
if (!map.has(leaderScore)) {
map.set(leaderScore, rank++);
}
}
return map;
}
