Map构建有向图

Map构建有向图

var graph = make(map[string]map[string]bool)

func addEdge(from, to string) {
    edges := graph[from]
    if edges == nil {
        edges = make(map[string]bool)
        graph[from] = edges
    }
    edges[to] = true
}

func hasEdge(from, to string) bool {
    return graph[from][to]
}