#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
const ll inf = 0x3f3f3f3f3f3f3f3f;
const int N = 85;
 
char s[N], w[N];
ull a[N], b[N];
ull base = 131;
 
ull qpow(ull a, ull b)
{
    ull ans = 1;
    while(b)
    {
        if(b & 1)
        {
            ans = ans * a;
        }
        a = a * a;
        b /= 2;
    }
    return ans;
}
 
void hashs(char s[], ull a[])
{
    int len = strlen(s + 1);
    a[0] = 0;
    for(int i = 1; i <= len; ++i)
    {
        a[i] = a[i - 1] * base + (ull)s[i];
    }
}
 
int main()
{
    scanf("%s", s + 1);
    scanf("%s", w + 1);
    hashs(s, a);
    hashs(w, b);
    int len1 = strlen(s + 1);
    int len2 = strlen(w + 1);
    int x = 0;
    int y = 0;
    for(int i = min(len1, len2); i > 0; --i)
    {
        ull tmp = b[len2] - b[len2 - i] * qpow(base, i);
        if(a[i] == tmp)
        {
            x = i;
            break;
        }
    }
    for(int i = min(len1, len2); i > 0; --i)
    {
        ull tmp = a[len1] - a[len1 - i] * qpow(base, i);
        if(b[i] == tmp)
        {
            y = i;
            break;
        }
    }
    cout<<max(x, y)<<'\n';
    return 0;
}