PROGRAMMING:The salvation of ZF series

The great wizard's prophecy tells ZF that the great devil will sacrifice mm, who was born on May 20, on the 14th of 13th, which is once in ten thousand years. He will gain unprecedented power to destroy the world, in order to save the world! He must be stopped!
Now, ZF is standing in front of the devil, and the final duel will begin! Smile Demon's HP is N1, attack is K1, ZF's HP is N2, attack is K2, ZF attacks first!
Can ZF stop the devil? It can output yes, not No
###Input format:
Smile Demon's HP is N1, attack is K1, ZF's HP is N2, attack is K2
###Output format:
Can ZF stop the devil? It can output yes, not No
###Input example:
Here is a set of inputs. For example:
```in
1 1 1 1
```
###Output example:
The corresponding output is given here. For example:
```out
yes
```







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