go语言实现

package main

import "fmt"

var(
    n int
    m int
)

const N int = 30
var g [N][N]bool
var dist [N][N]bool
var st [N]bool

func floyd(){
    for i := 0; i < n; i ++{
        for j := 0; j < n; j ++{
            dist[i][j] = g[i][j]
        }
    }

    for k := 0; k < n; k ++{
        for i := 0; i < n; i ++{
            for j := 0; j < n; j ++{
                dist[i][j] = dist[i][j] || (dist[i][k] && dist[k][j])
            }
        }
    }
}

func check() int{
    for i := 0; i < n; i ++{
        if dist[i][i]{
            return 2
        }
    }

    for i := 0; i < n; i ++{
        for j := 0; j < i; j ++{
            if !dist[i][j] && !dist[j][i]{
                return 0
            }
        }
    }

    return 1

}

func get_min() byte{

    for i := 0; i < n; i ++{
        if !st[i]{
            flag := true
            for j := 0; j < n; j ++{
                if !st[j] && dist[j][i]{
                    flag = false
                    break
                }
            }
            if (flag){
                st[i] = true
                return byte('A' + i)
            }
        }
    }
    return 'A'
}

func main(){

    for fmt.Scanf("%d%d", &n, &m);n != 0 && m != 0;fmt.Scanf("%d%d", &n, &m){
        for i := 0; i < n; i ++{
            for j := 0; j < n; j ++{
                g[i][j] = false
            }
        }
        var(
            temp int = 0
            t int
        )

        for i := 1; i <= m; i ++{
            var s string
            fmt.Scanf("%s", &s)
            a, b := s[0] - 'A', s[2] - 'A'
            if (temp == 0){
                g[a][b] = true
                floyd()
                temp = check()
                if (temp != 0){ 
                    t = i
                }
            }
        }

        if temp == 0{
            fmt.Printf("Sorted sequence cannot be determined.\n")
        } else if temp == 2{
            fmt.Printf("Inconsistency found after %d relations.\n", t)
        } else{
            for i := 0; i < n; i ++{
                st[i] = false
            }
            fmt.Printf("Sorted sequence determined after %d relations: ", t)
            for i := 0; i < n; i ++{
                fmt.Printf("%c", get_min())
            }
            fmt.Printf(".\n")
        }
    }
}