package mainimport "fmt"// bellman ford 算法计算单源点到其他点的距离，它无法处理含有负权回路的图
func main() {type edge struct {from, to, weight int}graphs := []edge{{from: 0, to: 1, weight: 6},{from: 1, to: 2, weight: -2},{from: 0, to: 2, weight: 3},{from: 2, to: 3, weight: 5},{from: 3, to: 1, weight: 7},}max := 0x3f3f3f3fdistance := make([]int, len(graphs))m := len(graphs)     // 边数, 暂时手动设置n := len(graphs) - 1 // 顶点数， 暂时手动设置for i := 0; i < n; i++ {distance[i] = max}distance[0] = 0 // 自己到自己的距离是0for i := 0; i < n; i++ {for j := 0; j < m; j++ {if distance[graphs[j].from] < max {distance[graphs[j].to] = min(distance[graphs[j].to], distance[graphs[j].from]+graphs[j].weight)}}}flag := falsefor i := 0; i < n; i++ {if distance[graphs[i].to] > distance[graphs[i].from]+graphs[i].weight {flag = true}}if flag {fmt.Println("含有负权回路")return}fmt.Println(distance[:n]) //return [0 6 3 8]
}func min(a int, b int) int {if a < b {return a}return b
}