#include <bits/stdc++.h>
#define MOD 1000000007

#define ll long long

using namespace std;

#define C 11000
#define D 2000

ll cl, dl;
char c[C] = {};
char d[D] = {};
char cc[C] = {};
char dd[D] = {};

ll best[C][D] = {};

ll calc_best(ll ci, ll di) {
    if(ci == cl) { best[ci][di] = dl-di; return dl-di; }
    if(di == dl) { best[ci][di] = cl-ci; return cl-ci; }

    if(best[ci][di] > -1)
        return best[ci][di];

    if(c[ci] == d[di] || c[ci] == '?' || d[di] == '?') {
        best[ci][di] = calc_best(ci+1, di+1);
        return best[ci][di];
    }

    ll del_both = 2+calc_best(ci+1, di+1);
    ll del_left = 1+calc_best(ci+1, di);
    ll del_right = 1+calc_best(ci, di+1);

    best[ci][di] = min(min(del_both, del_left), del_right);
    return best[ci][di];
}

int main(){
    for(ll i = 0; i < C; i++) {
        for(ll j = 0; j < D; j++) {
            best[i][j] = -1;
        }
    }

    scanf("%s", cc);
    scanf("%s", dd);

    ll ccl = strlen(cc);
    ll ddl = strlen(dd);

    ll e = 0;

    for(ll i = 0, ii = 0; i < ccl; i++) {
        ll n = cc[i] - '0';
        if(n >= 0 && n < 10) {
            e++;
            for(ll j = 0; j < n; j++) {
                c[i+ii] = '?';
                ii++;
            }
            ii--;
            continue;
        }

        c[i+ii] = cc[i];
    }

    for(ll i = 0, ii = 0; i < ddl; i++) {
        ll n = dd[i] - '0';
        if(n >= 0 && n < 10) {
            e++;
            for(ll j = 0; j < n; j++) {
                d[i+ii] = '?';
                ii++;
            }
            ii--;
            continue;
        }

        d[i+ii] = dd[i];
    }



    //printf("%s\n", c);
    //printf("%s\n", d);

    cl = strlen(c);
    dl = strlen(d);

    for(ll sm = cl+dl; sm >= 0; sm--) {
        for(ll di = min(dl, sm); di >= 0; di--) {
            ll ci = sm-di;
            if(ci > cl) break;
            calc_best(ci, di);
        }
    }

    printf("%lli\n", e+calc_best(0,0));

}