#include <bits/stdc++.h>

using namespace std;

int main()
{
    string fstr, sstr;
    cin >> fstr; cin >> sstr;
    vector<int>fsc(26,0), ssc(26,0);
    int i, result = 0;
    for(i = 0; i < fstr.size(); i++) fsc[fstr[i] - 'a']++;
    for(i = 0; i < sstr.size(); i++) ssc[sstr[i] - 'a']++;
    for(i = 0; i < 26; i++) result += abs(fsc[i] - ssc[i]);
    cout << result << endl;
    return 0;
}

sub makingAnagrams {
    my $s1 = shift;
    my $s2 = shift;
    my (%h1, %h2);
    my $cnt = 0;
    my $sum = 0;
    
    foreach (split("", $s1)) {
        $h1{$_} += 1;
    }
    foreach (split("", $s2)) {
        $h2{$_} += 1;
    }
    foreach my $k (keys %h1) {
        if (exists($h2{$k})) {
            $cnt += abs($h1{$k} - $h2{$k});
            delete $h1{$k};
            delete $h2{$k};
        }
        else {
            $cnt += $h1{$k};
            delete $h1{$k};
        }        
    }
    foreach my $k2 (keys %h2) {
        $sum += $h2{$k2};
    }
    return $cnt + $sum;
}

function makingAnagrams(s1: string, s2: string): number {
    // 0. define hash [m]
    let m = new Map<string, number>()

    // 1. counting [c]+ in [s1]
    // 2. counting [c]- in [s2]
    for (let c of s1) m.set(c, (m.get(c) || 0) + 1)
    for (let c of s2) m.set(c, (m.get(c) || 0) - 1)

    // 3. return sum of diff of each character between [s1]&[s2] that counted in [m]
    return Array.from(m.values()).reduce((p, c) => p + Math.abs(c), 0)
}

from collections import Counter

def makingAnagrams(s1, s2):
    count_s1 = Counter(s1)
    count_s2 = Counter(s2)
    dels = 0
    all_chars = set(count_s1.keys()).union(set(count_s2.keys()))
    for char in all_chars:
        dels += abs(count_s1[char] - count_s2[char])
    return dels

public static int makingAnagrams(String s1, String s2) {
    int commonCount = 0;
    HashMap<Character, Integer> map = new HashMap<>();
    int n = s1.length();
    int m = s2.length();
    
    for(int i = 0; i < n; i++){
      char c = s1.charAt(i);
      map.put(c, map.getOrDefault(c, 0) + 1 );
      }
    
    for(int i = 0; i < m; i++){
      char c = s2.charAt(i);
      if( map.containsKey(c) && map.get(c) > 0){
        commonCount++;
        map.put(c, map.get(c) - 1);
        }
      }
    
    return n + m - 2 * commonCount;

    }