Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Driver | Constructor | Laps | Time/Retired | Grid |
| --- | --- | --- | --- | --- |
| David Coulthard | McLaren - Mercedes | 72.0 | 1:38:05.538 | 2.0 |
| Mika Häkkinen | McLaren - Mercedes | 72.0 | +14.748 | 4.0 |
| Rubens Barrichello | Ferrari | 72.0 | +32.409 | 3.0 |
| Jacques Villeneuve | BAR - Honda | 72.0 | +1:01.322 | 7.0 |
| Ralf Schumacher | Williams - BMW | 72.0 | +1:03.981 | 5.0 |
| Jarno Trulli | Jordan - Mugen-Honda | 72.0 | +1:15.605 | 9.0 |
| Heinz-Harald Frentzen | Jordan - Mugen-Honda | 71.0 | +1 Lap | 8.0 |
| Jenson Button | Williams - BMW | 71.0 | +1 Lap | 10.0 |
| Giancarlo Fisichella | Benetton - Playlife | 71.0 | +1 Lap | 14.0 |
| Mika Salo | Sauber - Petronas | 71.0 | +1 Lap | 12.0 |
| Pedro Diniz | Sauber - Petronas | 71.0 | +1 Lap | 15.0 |
| Nick Heidfeld | Prost - Peugeot | 71.0 | +1 Lap | 16.0 |
| Eddie Irvine | Jaguar - Cosworth | 70.0 | +2 Laps | 6.0 |
| Jean Alesi | Prost - Peugeot | 70.0 | +2 Laps | 18.0 |
| Marc Gené | Minardi - Fondmetal | 70.0 | +2 Laps | 21.0 |
| Michael Schumacher | Ferrari | 58.0 | Engine | 1.0 |
| Pedro de la Rosa | Arrows - Supertec | 45.0 | Transmission | 13.0 |
| Alexander Wurz | Benetton - Playlife | 34.0 | Spun off | 17.0 |
| Gastón Mazzacane | Minardi - Fondmetal | 31.0 | Spun off | 22.0 |
| Jos Verstappen | Arrows - Supertec | 25.0 | Transmission | 20.0 |
| Johnny Herbert | Jaguar - Cosworth | 20.0 | Gearbox | 11.0 |
| Ricardo Zonta | BAR - Honda | 16.0 | Spun off | 19.0 |
Question:
What is the lowest number of laps obtained by driver Nick Heidfeld?
Answer:
71.0