Evaluate the similarity between them and classify them into classes from 0-5 as follows:
0 : The two sentences are completely dissimilar.
1 : The two sentences are not equivalent, but are on the same topic.
2 : The two sentences are not equivalent, but share some details.
3 : The two sentences are roughly equivalent, but some important information differs/missing.
4 : The two sentences are mostly equivalent, but some unimportant details differ.
5 : The two sentences are completely equivalent, as they mean the same thing.

Example Input: Sentence 1: 3 dead, 27 injured in SW China accident Sentence 2: 35 dead and 165 missing in India boat accident
Example Output: 0

Example Input: Sentence 1: A bird sits in a tree. Sentence 2: A bird sits in a leafless tree.
Example Output: 4

Example Input: Sentence 1: Australian among four on plane missing in Indonesia Sentence 2: Iranian painter Mansoureh Hosseini dies
Example Output:
0