example1.dot

graph {
  node [shape=circle];
  A -- B [label="2"];
  A -- C [label="2"];
  B -- C [label="2"];
  B -- D [label="2"];
  C -- E [label="1"];
  D -- E [label="2"];
  D -- G [label="1"];
  E -- F [label="2"];
  F -- G [label="2"];
}