PROGRAMMING:spring, summer, autumn and winter
In the sense of meteorology, spring is usually from March to may, summer is from June to August, autumn is from September to November, and winter is from December to February. Please output the corresponding season according to the year and month of the Gregorian calendar.
###Input format:
The input data format is fixed YYMM, that is: year accounts for 4 digits, month accounts for 2 digits, and there is no unreasonable input, such as 2017! @ @ $% 13 ^ & * and so on.
###Output format:
Output the season corresponding to the month (in English words, all in lowercase letters).
###Input sample 1:
```in
two hundred and one thousand nine hundred and one
```
###Output sample 1:
```out
winter
```
###Input sample 2:
```in
two hundred and one thousand eight hundred and seven
```
###Output sample 2:
```out
summer
```
answer：If there is no answer, please comment
###Input format:
The input data format is fixed YYMM, that is: year accounts for 4 digits, month accounts for 2 digits, and there is no unreasonable input, such as 2017! @ @ $% 13 ^ & * and so on.
###Output format:
Output the season corresponding to the month (in English words, all in lowercase letters).
###Input sample 1:
```in
two hundred and one thousand nine hundred and one
```
###Output sample 1:
```out
winter
```
###Input sample 2:
```in
two hundred and one thousand eight hundred and seven
```
###Output sample 2:
```out
summer
```
answer：If there is no answer, please comment