백준[node.js] > 15650번 제출

 

문제링크

https://www.acmicpc.net/problem/15650

 

풀이-1

let fs = require("fs");
let input = fs.readFileSync("/dev/stdin").toString();

const [N, M] = input.split(" ").map((n) => parseInt(n));

if (N === M) {
    answer = "";
    for (let i = 1; i <= N; ++i) {
        answer += `${i} `;
    }
    console.log(answer.trim());
} else {
    let answer = "";
    let rest = M;

    let recursive = (start, rest, arr) => {
        if (rest === 0) {
            answer = answer + `${arr.join(" ")}\n`;
        } else {
            for (let i = start; i <= N; ++i) {
                if (rest - 1 <= N - i) {
                    recursive(i + 1, rest - 1, [...arr, i]);
                }
            }
        }
    };
    recursive(1, rest, []);
    console.log(answer.trim());
}

 

풀이-2

같은 문제를 다른 방식으로도 풀어봤다.

let fs = require("fs");
let input = fs.readFileSync("/dev/stdin").toString();

const [N, M] = input.split(" ").map((n) => parseInt(n));

if (N === M) {
    answer = "";
    for (let i = 1; i <= N; ++i) {
        answer += `${i} `;
    }
    console.log(answer.trim());
} else {
    let visited = Array(N + 1).fill(false);

    let arr = [];
    let answer = "";

    let dfs = (start, cnt) => {
        if (cnt === M) {
            answer = answer + `${arr.join(" ")}\n`;
            return;
        }

        for (let i = start; i <= N; ++i) {
            if (!visited[i]) {
                visited[i] = true;
                arr.push(i);
                dfs(i + 1, cnt + 1);
                visited[i] = false;
                arr.pop();
            }
        }
    };

    dfs(1, 0);
    console.log(answer.trim());
}