word search solved

Author: mintheon

word-search/mintheon.java

@@ -0,0 +1,45 @@
+class Solution {
+  // BFS로 변환해서 다시 풀어볼 것
+  char[][] board;
+  boolean[][] visited;
+  int[] moveX = {-1, 1, 0, 0};
+  int[] moveY = {0, 0, -1, 1};
+  int row, col;
+
+  public boolean exist(char[][] board, String word) {
+    this.board = board;
+    this.row = board.length;
+    this.col = board[0].length;
+    this.visited = new boolean[row][col];
+
+    for(int y = 0; y < row; y++) {
+      for(int x = 0; x < col; x++) {
+        if(this.hasWord(y, x, word, 0)) {
+          return true;
+        }
+      }
+    }
+
+    return false;
+  }
+
+  private boolean hasWord(int y, int x, String word, int index) {
+    if(index >= word.length()) {
+      return true;
+    }
+
+    if(x < 0 || x >= col || y < 0 || y >= row || visited[y][x] || board[y][x] != word.charAt(index)) {
+      return false;
+    }
+
+    this.visited[y][x] = true;
+    for(int i = 0; i < 4; i++) {
+      if(this.hasWord(y + moveY[i], x + moveX[i], word, index + 1)) {
+        return true;
+      }
+    }
+
+    this.visited[y][x] = false;
+    return false;
+  }
+}