Merge branch 'main' of https://github.com/prgrms-web-devcourse/FEDC5_JavaScript_coding_test_study

Author: ienrum

Diff for: 4주차/박종운/골드4__사회망_서비스.js

@@ -0,0 +1,42 @@
+const readline = require('readline');
+
+const rl = readline.createInterface({
+  input: process.execArgv.includes("--stack-size=65536") ? 
+    process.stdin : require('fs').createReadStream(__dirname + '/input.txt'),
+  output: process.stdout
+});
+
+let N;
+let graph;
+let dp;
+let visited;
+
+function dfs(cur) {
+  visited[cur] = true;
+
+  for (const child of graph[cur]) {
+    if (!visited[child]) {
+      dfs(child);
+      dp[cur][0] += dp[child][1];
+      dp[cur][1] += Math.min(...dp[child]);
+    }
+  }
+}
+
+rl.question('', input => {
+  N = parseInt(input);
+  graph = Array.from({ length: N + 1 }, () => []);
+  dp = Array.from({ length: N + 1 }, () => [0, 1]);
+  visited = Array(N + 1).fill(false);
+
+  rl.on('line', line => {
+    const [u, v] = line.split(' ').map(Number);
+    graph[u].push(v);
+    graph[v].push(u);
+  }).on('close', () => {
+    dfs(1);
+    console.log(Math.min(...dp[1]));
+
+    process.exit();
+  });
+});

Diff for: 4주차/박종운/레벨3__길_찾기_게임.js

@@ -0,0 +1,28 @@
+function solution(nodeinfo) {
+    const nodes = nodeinfo.map((el, i) => [i+1, ...el]);
+    
+    const sorted = nodes.sort((a, b) => b[2] === a[2] ? a[1] - b[1] : b[2] - a[2]);
+
+    const preorder = [];
+    const postorder = [];
+
+    function traverse(arr) {
+        if(!arr.length) return;
+        
+        const current = arr[0];
+        
+        preorder.push(current[0]);
+        
+        const newLeft = arr.filter(el => el[2] < current[2] && el[1] < current[1]);
+        const newRight = arr.filter(el => el[2] < current[2] && el[1] > current[1] );
+        
+        traverse(newLeft);
+        traverse(newRight);
+        
+        postorder.push(current[0]);
+    }
+
+    traverse(sorted);
+    
+    return [preorder, postorder];
+}

Diff for: 4주차/박종운/실버2__트리의_부모_찾기.js

@@ -0,0 +1,45 @@
+const local_input = `
+7
+1 6
+6 3
+3 5
+4 1
+2 4
+4 7
+`;
+
+const input = process.execArgv.includes("--stack-size=65536")
+  ? require("fs").readFileSync("dev/stdin").toString()
+  : local_input;
+
+const lines = input.trim().split('\n');
+
+const N = Number(lines[0]);
+const edges = lines.slice(1).map(el => el.split(' ').map(Number));
+
+const graph = {};
+
+edges.forEach(el => {
+  if(!graph[el[0]]) graph[el[0]] = [];
+  if(!graph[el[1]]) graph[el[1]] = [];
+  graph[el[0]].push(el[1])
+  graph[el[1]].push(el[0])
+})
+
+const queue = [1];
+const visited = new Set([1]);
+const parentNodes = [];
+
+while(queue.length) {
+  const currentNode = queue.shift();
+  const childNodes = graph[currentNode].filter(childNode => !visited.has(childNode));
+
+  childNodes.forEach(childNode => {
+    parentNodes[childNode] = currentNode;
+    queue.push(childNode);
+  })
+  
+  visited.add(currentNode);
+}
+
+console.log(parentNodes.slice(2).join('\n'))