If condition for elements within set

I am working within a for loop with index j in 1:N and I also have a sample v <- sample(1:N,n,F). I'm looking for some sort of if else statement that works this way:

for(j in 1:N){
  if(j in v){
      ...
  }else{ ... }

The problem with this is that if doesn't work with in. Also I need to work with j in a chronological way therefore I can't work with two different loops, one for j in 1:N and another for j in v.