@NGPH - A graph format
Specifies the network topology.
| Data | Type | Description |
|---|---|---|
| @NGPH | 5 fixed characters | A tag |
| N | integer | Number of nodes in the graph |
| i j | A pair of integers separated by a space character. | An edge connecting nodes i and j. |
| … | (repeat) | |
| -1 -1 | A pair of integers separated by a space character. | Terminator |