(function(input) {
  'use strict';

  //var input = '10\n8 4 8 3 8 2 8 1 8 4\n'
  //var input = '4\n3 2 3 1\n'
  //var input = '6\n105 119 105 119 105 119\n'
  //var input = '6\n1 1 1 1 1 1\n'
  //var input   = '6\n4 2 4 3 4 2\n'

  var n = 0
  var ary = []
  input.split("\n").some(function(line) {
    if (n == 0) {
      n = parseInt(line, 10)
    } else {
      ary = line.split(' ').map((x) => { return parseInt(x, 10)})
      return true
    }
  })

  var oHash = {}
  var eMaxKey = 0
  var eHash = {}
  var oMaxKey = 0
  for (var i = 0, len = ary.length; i < len; i++) {
    if (i % 2 == 1) {
      if (eHash[ary[i]] === undefined) {
        eHash[ary[i]] = 0
      }
      eHash[ary[i]] += 1
      if (eMaxKey < eHash[ary[i]]) {
        eMaxKey = ary[i]
      }
    } else {
      if (oHash[ary[i]] === undefined) {
        oHash[ary[i]] = 0
      }
      oHash[ary[i]] += 1
      if (oMaxKey < oHash[ary[i]]) {
        oMaxKey = ary[i]
      }
    }
  }

  var oLength = Object.keys(oHash).length
  var eLength = Object.keys(eHash).length
  if (oLength == 1 && eLength == 1) {
    if (eMaxKey == oMaxKey) {
      console.log(n/2)
    } else {
      console.log(0)
    }
    return
  }

  var maxKey = (eMaxKey > oMaxKey) ? eMaxKey : oMaxKey
  var hash = (eMaxKey > oMaxKey) ? oHash : eHash

  var objLength = Object.keys(hash).length
  if (objLength == 1) {
    console.log(n/2)
    return
  }

  // delete hash[maxKey]
  // objLength -= 1
  //

  var secondMax = -1
  if (objLength == 1) {
    for (var i in hash) {
      secondMax = i
    }
  } else {
    for (var i in hash) {
      if (secondMax == -1) {
        secondMax = hash[i]
        continue
      }
      if (secondMax < hash[i]) {
        secondMax = i
      }
    }
  }

  delete hash[secondMax]
  objLength -= 1

  // console.log('secondMax')
  // console.log(secondMax)
  // console.log(hash)

  console.log(objLength)

})(require('fs').readFileSync('/dev/stdin', 'utf8'))
