word-search

Author: jun0811

word-search/jun0811.js

@@ -0,0 +1,58 @@
+/**
+ * @param {character[][]} board
+ * @param {string} word
+ * @return {boolean}
+ */
+
+const directions = [
+  [0, -1],
+  [1, 0],
+  [-1, 0],
+  [0, 1],
+];
+
+var exist = function (board, word) {
+  const cols = board[0].length; // 가로 (열 개수)
+  const rows = board.length; // 세로 (행 개수)
+  let res = false;
+
+  for (let col = 0; col < cols; col++) {
+    for (let row = 0; row < rows; row++) {
+      if (board[row][col] != word[0]) continue;
+
+      const visited = Array.from({ length: rows }, () =>
+        Array(cols).fill(false)
+      );
+      if (res) break;
+      dfs(row, col, board[row][col], visited);
+    }
+  }
+
+  function check(row, col) {
+    if (!(row >= 0 && row < rows)) return false;
+    if (!(col >= 0 && col < cols)) return false;
+    return true;
+  }
+
+  function dfs(row, col, str, visited) {
+    if (str == word) {
+      res = true;
+      return;
+    }
+    if (str.length >= word.length) return;
+    visited[row][col] = true;
+
+    for (const direction of directions) {
+      const [d_r, d_c] = direction;
+      const newCol = col + d_c;
+      const newRow = row + d_r;
+
+      if (check(newRow, newCol) && !visited[newRow][newCol]) {
+        dfs(newRow, newCol, str + board[newRow][newCol], visited);
+      }
+    }
+    visited[row][col] = false;
+  }
+
+  return res;
+};