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@@ -0,0 +1,48 @@
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+package main
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+
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+import (
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+ "fmt"
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+ "math"
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+)
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+
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+func main() {
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+ var n, m, src int
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+ fmt.Scan(&n, &m, &src)
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+ adj := make([][]int, n)
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+ length := make([][]int, n)
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+ for i := range length {
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+ length[i] = make([]int, n)
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+ }
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+ for i := 0; i < m; i++ {
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+ var u, v, l int
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+ fmt.Scan(&u, &v, &l)
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+ adj[u] = append(adj[u], v)
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+ length[u][v] = l
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+ }
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+ dist, prev := bellmanFord(adj, length, src)
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+ fmt.Println(dist)
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+ fmt.Println(prev)
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+}
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+
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+func bellmanFord(adj [][]int, length [][]int, src int) ([]int, []int) {
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+ n := len(adj)
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+ dist := make([]int, n)
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+ prev := make([]int, n)
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+ for i := 0; i < n; i++ {
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+ dist[i] = math.MaxInt32
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+ prev[i] = -1
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+ }
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+ dist[src] = 0
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+ for updated := true; updated; updated = false {
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+ for u := range adj {
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+ for _, v := range adj[u] {
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+ if alt := dist[u] + length[u][v]; alt < dist[v] {
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+ dist[v] = alt
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+ prev[v] = u
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+ updated = true
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+ }
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+ }
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+ }
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+ }
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+ return dist, prev
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+}
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