79. Word Search.go

package leetcode

vardir= [][]int{
 {-1, 0},
 {0, 1},
 {1, 0},
 {0, -1},
}

funcexist(board [][]byte, wordstring) bool {
visited:=make([][]bool, len(board))
fori:=0; i<len(visited); i++ {
visited[i] =make([]bool, len(board[0]))
 }
fori, v:=rangeboard {
forj:=rangev {
ifsearchWord(board, visited, word, 0, i, j) {
returntrue
 }
 }
 }
returnfalse
}

funcisInBoard(board [][]byte, x, yint) bool {
returnx>=0&&x<len(board) &&y>=0&&y<len(board[0])
}

funcsearchWord(board [][]byte, visited [][]bool, wordstring, index, x, yint) bool {
ifindex==len(word)-1 {
returnboard[x][y] ==word[index]
 }
ifboard[x][y] ==word[index] {
visited[x][y] =true
fori:=0; i<4; i++ {
nx:=x+dir[i][0]
ny:=y+dir[i][1]
ifisInBoard(board, nx, ny) &&!visited[nx][ny] &&searchWord(board, visited, word, index+1, nx, ny) {
returntrue
 }
 }
visited[x][y] =false
 }
returnfalse
}