How to make an equation in R for each individual cell

I have 2 columns of different size, A and B.

A | B

5 | 4
1 | 2
3 |

How do I say If CellA is < CellB then give me CellB-CellA? So it calculates:

"5(A1) is bigger than 4(B1) and 2(B2)" so no results

"1(A2) is smaller than 4(B1) and 2(B2)" so we have 3 and 1

"3(A3) is smaller than 4(B1) and bigger than 2(B2)" so we have 1

Result = (3, 1, 1)

The closest I got was: if (A < B) {B - A}

But that only works with columns of same size, I want each individual cell of Column A to interact with each individual cell of column B. How can I do that?

Solution

Since the columns of different sizes then it must be list and not data.frame so the solution :

listAB <- list(A = c(5,1,3) , B = c(4,2))

equ <- function(li){
  result <- vector("numeric")
  for (x in li$A){
    result <- append(result , sapply(li$B , function(y) if(x < y) y - x))
  }
  unlist(result)
}

equ(listAB)
#> [1] 3 1 1

^{Created on 2022-05-29 by the reprex package (v2.0.1)}