R: make this loop go faster

Currently I am working on a loop. I tried making this with a apply function but it would not work. This loop takes ages. Also I cannot work with the ifelse function as I have nested two functions within 1 statement.

Thanks in advance

I am trying to make a code which countsdown the values in the columns to 0. When a value hits 0 it has to reset to 7 and create a new column with a value of 8. (i'm doing this for the advent of code 2021 event)

dag6 <- data.frame(var1 = 2,
                  var2 = 5,
                  var3 = 6,
                  var4 = 1,
                  var5 = 3,
                  var6 = 6) # Example data as loaded from file

row <- as.data.frame(8)

for (j in 1:80) {
  print(j)
  for (i in 1:ncol(dag6)) 
  {if (dag6[1,i] == 0) {
    dag6[1,i] <- 7
    dag6 <- cbind(dag6, row)
  }
    else {dag6[1,i] <- dag6[1,i]-1}
  }
}