# Shortest Common Supersequence

The shortest common supersequence (SCS) of two sequences `X` and `Y` 
is the shortest sequence which has `X` and `Y` as subsequences.

In other words assume we're given two strings str1 and str2, find 
the shortest string that has both str1 and str2 as subsequences.

This is a problem closely related to the longest common 
subsequence problem.

## Example

```
Input:   str1 = "geek",  str2 = "eke"
Output: "geeke"

Input:   str1 = "AGGTAB",  str2 = "GXTXAYB"
Output:  "AGXGTXAYB"
```

## References

- [GeeksForGeeks](https://www.geeksforgeeks.org/shortest-common-supersequence/)