Task: Question Answering
Input (English): Passage: The 6000-mark war  was a war between Denmark and Sweden which took place from 1276 to 1278. It started because of a disagreement over an agreed sum of 6,000 silver marks for Danish assistance to Magnus Birgersson in the battle against Valdemar Birgersson in 1275. 
Question: How many countries fought in the 6000-mark war? 
Answer type: Number 
Output (English): 2.