Dataframe subsetting on a variable with the same value

Question

I have a simple data frame like this:

col1    col2
a       1   
b       2
a       2

I'll refer to this data frame as table. I am trying to create variables a1 and a2 where the value of a1 would be 1 in this instance and the value of a2 would be 2. My current attempt is this to get a1 and a2:

for (i in 1:nrow(table)) {
  
  # Getting a1
  if (col1 == 'a') {
    a1 <- as.numeric(table %>% dplyr::select(col2))
  } else {
    if (a1 != 0) {
      a1 <- a1
    } else {
      a1 <- 0
    }
  }

 # Getting a2
 if (col1 == 'a' & a1 != 0) {
    a2 <- as.numeric(table %>% dplyr::select(col2))
  } else {
    if (a2 != 0) {
      a2 <- a2
    } else {
      a2 <- 0
    }
  }

}

With this I get a1 and a2 to be 2. So the loops are correctly identifying the 2nd instance where col1 = 'a' but for a1 I need the first instance where col1 = 'a' which keeps getting overwritten.

Any suggestions?