word search golang

go/79-Word-Search.go

@@ -0,0 +1,38 @@
+package main
+
+func exist(board [][]byte, word string) bool {
+	n := len(board)
+	m := len(board[0])
+
+	var dfs func(i int, j int, curr int) bool
+	dfs = func(i int, j int, curr int) bool {
+		if i < 0 || j < 0 || i >= n || j >= m || curr == len(word) {
+			return false
+		}
+		if board[i][j] != word[curr] || board[i][j] == '*' {
+			return false
+		}
+		if curr == len(word)-1 {
+			return true
+		}
+
+		tmp := board[i][j]
+		board[i][j] = '*'
+
+		res := dfs(i+1, j, curr+1) || dfs(i-1, j, curr+1) || dfs(i, j-1, curr+1) || dfs(i, j+1, curr+1)
+
+		board[i][j] = tmp
+
+		return res
+	}
+
+	for i := 0; i < n; i++ {
+		for j := 0; j < m; j++ {
+			if dfs(i, j, 0) {
+				return true
+			}
+		}
+	}
+
+	return false
+}