Initial data commit

Task/Floyd-Warshall-algorithm/Groovy/floyd-warshall-algorithm.groovy

@@ -0,0 +1,61 @@
+class FloydWarshall {
+    static void main(String[] args) {
+        int[][] weights = [[1, 3, -2], [2, 1, 4], [2, 3, 3], [3, 4, 2], [4, 2, -1]]
+        int numVertices = 4
+
+        floydWarshall(weights, numVertices)
+    }
+
+    static void floydWarshall(int[][] weights, int numVertices) {
+        double[][] dist = new double[numVertices][numVertices]
+        for (double[] row : dist) {
+            Arrays.fill(row, Double.POSITIVE_INFINITY)
+        }
+
+        for (int[] w : weights) {
+            dist[w[0] - 1][w[1] - 1] = w[2]
+        }
+
+        int[][] next = new int[numVertices][numVertices]
+        for (int i = 0; i < next.length; i++) {
+            for (int j = 0; j < next.length; j++) {
+                if (i != j) {
+                    next[i][j] = j + 1
+                }
+            }
+        }
+
+        for (int k = 0; k < numVertices; k++) {
+            for (int i = 0; i < numVertices; i++) {
+                for (int j = 0; j < numVertices; j++) {
+                    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)
+    }
+
+    static void printResult(double[][] dist, int[][] next) {
+        println("pair     dist    path")
+        for (int i = 0; i < next.length; i++) {
+            for (int j = 0; j < next.length; j++) {
+                if (i != j) {
+                    int u = i + 1
+                    int v = j + 1
+                    String path = String.format("%d -> %d    %2d     %s", u, v, (int) dist[i][j], u)
+                    boolean loop = true
+                    while (loop) {
+                        u = next[u - 1][v - 1]
+                        path += " -> " + u
+                        loop = u != v
+                    }
+                    println(path)
+                }
+            }
+        }
+    }
+}