#include <bits/stdc++.h>
using namespace std;
long long MOD_EXPO(long long b, long long p, long long m) {
  if (p == 0) return 1;
  long long ret = MOD_EXPO(b, p / 2, m) % m;
  ret = (ret * ret) % m;
  return ((p & 1) ? (ret * b) % m : ret % m);
}
long long POWER(long long N, long long K) {
  long long i, ans = 1;
  for (i = 1; i <= K; i++) ans *= N;
  return ans;
}
int SET(int N, int pos) { return (N | (1 << pos)); }
int RESET(int N, int pos) { return (N & !(1 << pos)); }
bool CHECK(int N, int pos) { return (N & (1 << pos)); }
int dx4[] = {1, -1, 0, 0};
int dy4[] = {0, 0, 1, -1};
int dx6[] = {0, 0, 1, -1, 0, 0};
int dy6[] = {1, -1, 0, 0, 0, 0};
int dz6[] = {0, 0, 0, 0, 1, -1};
int dx8[] = {1, -1, 0, 0, -1, 1, -1, 1};
int dy8[] = {0, 0, 1, -1, 1, 1, -1, -1};
int dkx8[] = {-1, 1, -1, 1, -2, -2, 2, 2};
int dky8[] = {2, 2, -2, -2, 1, -1, 1, -1};
int tc = 1;
const double eps = 1e-9;
const double pi = acos(-1.0);
const long long int mx = 1e5;
const long long int mod = 1e9 + 7;
int main() {
  int i, n, k, cnt;
  string str, outs;
  char ch, cc;
  while (cin >> str >> n) {
    map<char, int> mp;
    for (i = 0; i < str.size(); i++) mp[str[i]]++;
    for (i = 0; i < 26; i++) {
      k = INT_MAX;
      for (ch = 'a'; ch <= 'z'; ch++) {
        if (mp[ch] < k && mp[ch]) {
          k = mp[ch];
          cc = ch;
        }
      }
      if (k <= n) {
        n -= k;
        mp[cc] = 0;
      }
    }
    outs = "";
    cnt = 0;
    for (ch = 'a'; ch <= 'z'; ch++) {
      if (mp[ch]) cnt++;
    }
    for (i = 0; i < str.size(); i++) {
      if (mp[str[i]]) {
        outs += str[i];
        mp[str[i]]--;
      }
    }
    cout << cnt << "\n";
    cout << outs << "\n";
  }
  return 0;
}
