I have a problem that i can't solve and i hope someone can help me...

I have this matrix

A B
1 JJ 45
2 FN 35
3 FN 22
4 JJ 99
5 FN 30

And want to X and Y to be 45 and 35. I.e. that the first value in the column
is but in column B in matrix below

A B
1 FN Y
2 JJ X

Thanks in advance

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