You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: d.go
    path of file: ./repos/codeforces-go/leetcode/weekly/292/d
    
    the code of the file until where you have to start completion: package main

// github.com/EndlessCheng/codeforces-go
func hasValidPath(grid [][]byte) bool {
	m, n := len(grid), len(grid[0])
	if (m+n)%2 == 0 || grid[0][0] == ')' || grid[m-1][n-1] == '(' { // 剪枝
		return false
	}

	vis := make([][][]bool, m)
	for i := range vis {
		vis[i] = make([][]bool, n)
		for j := range vis[i] {
			vis[i][j] = make([]bool, (m+n+1)/2)
		}
	}
	var dfs func(x, y, c int) bool
	dfs = func(x, y, c int) bo
    
func hasValidPath(grid [][]byte) bool {
	m, n := len(grid), len(grid[0])
	if (m+n)%2 == 0 || grid[0][0] == ')' || grid[m-1][n-1] == '(' { // 剪枝
		return false
	}

	vis := make([][][]bool, m)
	for i := range vis {
		vis[i] = make([][]bool, n)
		for j := range vis[i] {
			vis[i][j] = make([]bool, (m+n+1)/2)
		}
	}
	var dfs func(x, y, c int) bool
	dfs = func(x, y, c int) bool {
		if c > m-x+n-y-1 { // 剪枝：即使后面都是 ')' 也不能将 c 减为 0
			return false
		}
		if x == m-1 && y == n-1 { // 终点
			return c == 1 // 终点一定是 ')'
		}
		if vis[x][y][c] { // 重复访问
			return false
		}
		vis[x][y][c] = true
		if grid[x][y] == '(' {
			c++
		} else if c--; c < 0 { // 非法括号字符串
			return false
		}
		return x < m-1 && dfs(x+1, y, c) || y < n-1 && dfs(x, y+1, c) // 往下或者往右
	}
	return dfs(0, 0, 0) // 起点
}