PROGRAMMING:Continuity and problem

###Problem description
Give you a continuous integer, can you find the sum of them?
###Input format:
Two integers a and B are given in one line (a < = B and the absolute value does not exceed 10000).
###Output format:
An integer, that is, the sum of all consecutive integers from a to B (including a and b).
###Input example:
```in
1 10
```
###Output example:
```out
fifty-five
```
###Input example:
```in
-10 10
```
###Output example:
```out
0
```







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