[Daily 24] Jiho 2Q

Jiho/Day23/백준_10816.js

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+const fs = require("fs");
+const input = fs
+  .readFileSync(process.platform === "linux" ? "/dev/stdin" : "../input.txt")
+  .toString()
+  .trim()
+  .split("\n");
+
+const N = parseInt(input[0]);
+const carr = input[1].trim().split(" ").map(Number);
+const M = parseInt(input[2]);
+const nums = input[3].trim().split(" ").map(Number);
+
+// Map 만들기
+let map = new Map();
+for (const val of carr) {
+  map.set(val, (map.get(val) | 0) + 1);
+}
+
+// 결과 만들기
+const result = [];
+for (const num of nums) {
+  result.push(map.get(num) | 0);
+}
+console.log(result.join(" "));

Jiho/Day23/백준_4963.js

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+const fs = require("fs");
+const input = fs
+  .readFileSync(process.platform === "linux" ? "/dev/stdin" : "../input.txt")
+  .toString()
+  .trim()
+  .split("\n");
+
+// 저장
+let answers = [];
+while (true) {
+  const [w, h] = input.shift()?.split(" ").map(Number);
+
+  if (w === 0 && h === 0) {
+    break;
+  }
+  let map = Array.from(new Array(h), () => new Array(w));
+  let visited = Array.from(new Array(h), () => new Array(w).fill(false));
+
+  for (let i = 0; i < h; i++) {
+    const arr = input.shift()?.split(" ").map(Number);
+    for (let j = 0; j < w; j++) {
+      map[i][j] = arr[j];
+    }
+  }
+
+  const BFS_FindConnected = (startRow, startCol, map, visited) => {
+    const dr = [0, 1, 1, 1, 0, -1, -1, -1];
+    const dc = [1, 1, 0, -1, -1, -1, 0, 1];
+    visited[startRow][startCol] = true;
+    let queue = [[startRow, startCol]];
+    while (queue.length) {
+      const [row, col] = queue.shift();
+
+      for (let i = 0; i < 8; i++) {
+        const [nrow, ncol] = [row + dr[i], col + dc[i]];
+        if (
+          nrow >= 0 &&
+          nrow < h &&
+          ncol >= 0 &&
+          ncol < w &&
+          !visited[nrow][ncol] &&
+          map[nrow][ncol] === 1
+        ) {
+          visited[nrow][ncol] = true;
+          queue.push([nrow, ncol]);
+        }
+      }
+    }
+  };
+
+  // Execute BFS
+  let answer = 0;
+  for (let row = 0; row < h; row++) {
+    for (let col = 0; col < w; col++) {
+      if (!visited[row][col] && map[row][col] === 1) {
+        answer++;
+        BFS_FindConnected(row, col, map, visited);
+      }
+    }
+  }
+  answers.push(answer);
+}
+console.log(answers.join("\n"));

Jiho/Day24/Leetcode_39. Combination Sum.js

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+var combinationSum = function (candidates, target) {
+  const len = candidates.length;
+  let answer = [];
+  let accumulate = [];
+  function backtracking(remain, arr, index) {
+    if (remain === 0) {
+      answer.push(arr);
+      return;
+    }
+    if (index < 0) {
+      return;
+    }
+    const val = candidates[index];
+    const q = Math.floor(remain / val); // q번 만큼 backtracking 해야함
+
+    for (let i = q; i >= 0; i--) {
+      const new_arr = [...arr];
+      for (let j = 0; j < i; j++) {
+        new_arr.push(val);
+      }
+
+      backtracking(remain - i * val, new_arr, index - 1);
+    }
+  }
+
+  backtracking(target, accumulate, len - 1);
+  return answer;
+};
+
+console.log(combinationSum([2], 1));

Jiho/Day24/Leetcode_78. Subsets.js

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+var subsets = function (nums) {
+  let accumulate = [];
+  let answer = [];
+  function backtracking(arr, index) {
+    // 마지막
+    if (index === nums.length) {
+      answer.push(arr);
+      return;
+    }
+    const cpy = [...arr];
+    backtracking(cpy, index + 1);
+    arr.push(nums[index]);
+    backtracking(arr, index + 1);
+  }
+  backtracking(accumulate, 0);
+
+  return answer;
+};
+
+console.log(subsets([1, 2, 3]));