[baekjoon] 2910 빈도 정렬 (Javascript,C++)

2910번: 빈도 정렬 (acmicpc.net)

2910번: 빈도 정렬

 

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접근 : 정렬

 

1. map활용법에 익숙해지기 좋은 문제였다.

2. 주어진 조건을 통해 커스텀 정렬

 

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Javascript

let input = require("fs")
  .readFileSync("input.txt") //"/dev/stdin"
  .toString()
  .split("\n")
  .map((val) => val.trim());

let [n, c] = input
  .shift()
  .split(" ")
  .map((v) => +v);
let arr = input[0].split(" ").map((v) => +v);
function solution() {
  let answer = [];
  let hs = new Map();

  for (let i = 0; i < n; i++) {
    let temp = arr[i];
    if (hs.has(temp)) {
      let [cnt, idx] = hs.get(temp);
      cnt++;
      hs.set(temp, [cnt, idx]);
    } else {
      hs.set(temp, [1, i]);
    }
  }

  let tmp = [];
  for (const [key, val] of hs) {
    tmp.push([key, val]);
  }

  tmp.sort((a, b) => {
    if (a[1][0] === b[1][0]) return a[1][1] - b[1][1];
    else return b[1][0] - a[1][0];
  });

  for (const [key, [cnt, idx]] of tmp) {
    for (let i = 0; i < cnt; i++) {
      answer.push(key);
    }
  }

  console.log(answer.join(" "));
}

solution();

---

C++

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const ll INF = 1e18;

int n,c,a[1004];
vector<pair<int,int>> v;
map<int,int> m,mp;

bool cmp(pair<int,int> a, pair<int,int>b){
  if(a.first==b.first) return mp[a.second] < mp[b.second];
  return a.first>b.first;
}

int main()
{
  freopen("input.txt", "r", stdin); //제출 시 삭제

    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);

  cin>>n>>c;
  for(int i=0;i<n;i++){
    cin>>a[i];
    m[a[i]]++;
    if(mp[a[i]]==0) mp[a[i]]=i+1;
  }

  for(auto it:m){
    v.push_back({it.second, it.first});
  }

  sort(v.begin(),v.end(),cmp);

  for(auto i:v){
    for(int j=0;j<i.first;j++){
      cout<<i.second<<" ";
    }
  }


  return 0;
}