import strutils, sequtils

let N, A = stdin.readLine.split.map parseInt
var arr = newSeqWith(0, 0)

for i in 0 ..< N[0]:
  arr.add i + 1

for i in 0 ..< A.len:
  let idx = A[i] - 1
  swap(arr[0], arr[idx])

echo arr[0]