Add floyd warshall

Signed-off-by: Bruno Freitas Tissei <bft15@inf.ufpr.br>

graph/floyd_warshall.cpp

+/**
+ * Floyd Warshall Algorithm
+ *
+ * Complexity (Time): O(n^3)
+ * Complexity (Space): O(n^2)
+ */
+
+int dist[MAX][MAX];
+int graph[MAX][MAX];
+
+// Build dist matrix
+int floyd_warshall(int n) {
+  for (int i = 0; i < n; ++i)
+    for (int j = 0; j < n; ++j)
+      dist[i][j] = graph[i][j];
+
+  for (int k = 0; k < n; ++k)
+    for (int i = 0; i < n; ++i)
+      for (int j = 0; j < n; ++j)
+        if (dist[i][k] + dist[k][j] < dist[i][j])
+          dist[i][j] = dist[i][k] + dist[k][j];
+}

graph/kruskal.cpp

@@ -17,6 +17,7 @@ bool cmp(iii a, iii b) {
   //* return a.se > b.se
 }
 
+// Return value of MST and build mst vector with edges that belong to the tree
 int kruskal() {
   sort(edges.begin(), edges.end(), cmp);