You are given a string S consisting of lowercase English letters.
Another string T is initially empty.
Determine whether it is possible to obtain S = T by performing the following operation an arbitrary number of times:
- Append one of the following at the end of T: dream, dreamer, erase and eraser.

-----Constraints-----
- 1≦|S|≦10^5
- S consists of lowercase English letters.

-----Input-----
The input is given from Standard Input in the following format:
S

-----Output-----
If it is possible to obtain S = T, print YES. Otherwise, print NO.

-----Sample Input-----
erasedream

-----Sample Output-----
YES

Append erase and dream at the end of T in this order, to obtain S = T.

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