n-皇后问题-dfs-golang

blablabla

golang

package main

import "fmt"

var n int
var grid [][]string  //棋盘
var cor, dg, udg []bool  //列，两条对角线

func main(){
    fmt.Scanf("%d", &n)
    grid = make([][]string, n)
    for i := 0; i < n; i ++{
        grid[i] = make([]string, n)
    }
    cor, dg, udg = make([]bool, n), make([]bool, n*2), make([]bool, n*2)
    //棋盘
    for i := 0; i < n; i++{
        for j:= 0; j < n; j++{
            grid[i][j] = "."
        }
    }

    dfs(0)
}

func dfs(r int){
    if r == n{
        for i := 0; i < n; i++{
            for j:= 0; j < n; j++{
                fmt.Printf("%s", grid[i][j])
            }
            fmt.Println()
        }
        fmt.Println()
    }

    for i := 0; i < n; i++{
        if !cor[i] && !dg[r+i] && !udg[r+n-i]{
            grid[r][i] = "Q"
            cor[i]  = true
            dg[r+i] = true
            udg[r+n-i] = true
            dfs(r+1)
            grid[r][i] = "."
            cor[i]  = false
            dg[r+i] = false
            udg[r+n-i] = false
        }
    }
}