Data update

Task/Floyd-Warshall-algorithm/Swift/floyd-warshall-algorithm.swift

@@ -0,0 +1,51 @@
+func floydWarshall(_ weights: [[Int]], _ numVertices: Int) {
+    var dist = Array(repeating: Array(repeating: Double.infinity, count: numVertices), count: numVertices)
+    var next = Array(repeating: Array(repeating: 0, count: numVertices), count: numVertices)
+
+    for weight in weights {
+        dist[weight[0] - 1][weight[1] - 1] = Double(weight[2])
+    }
+
+    for i in 0..<numVertices {
+        for j in 0..<numVertices {
+            if i != j {
+                next[i][j] = j + 1
+            }
+        }
+    }
+
+    for k in 0..<numVertices {
+        for i in 0..<numVertices {
+            for j in 0..<numVertices {
+                if dist[i][k] + dist[k][j] < dist[i][j] {
+                    dist[i][j] = dist[i][k] + dist[k][j]
+                    next[i][j] = next[i][k]
+                }
+            }
+        }
+    }
+
+    printResult(dist, next)
+}
+
+func printResult(_ dist: [[Double]], _ next: [[Int]]) {
+    print("pair     dist    path")
+    for i in 0..<next.count {
+        for j in 0..<next.count {
+            if i != j {
+                var u = i + 1
+                let v = j + 1
+                var path = "\(u) -> \(v)    \(Int(dist[i][j]))     \(u)"
+                repeat {
+                    u = next[u - 1][v - 1]
+                    path += " -> \(u)"
+                } while u != v
+                print(path)
+            }
+        }
+    }
+}
+
+let weights = [[1, 3, -2], [2, 1, 4], [2, 3, 3], [3, 4, 2], [4, 2, -1]]
+let numVertices = 4
+floydWarshall(weights, numVertices)