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#include <bits/stdc++.h>
using namespace std;
typedef long long ll;

int num(char c) {
    return int(c - '0');
}

int main() {
    ios_base::sync_with_stdio(false); cin.tie(NULL);
    string a, b, c; cin >> a >> b >> c;
    int n = int(a.length());

    ll s0 = 0ll, s1 = 0ll, ans = 0ll;
    for(int i = n - 1; i >= 0; --i) {
        ll s00 = s0, s11 = s1;
        s0 = 0ll, s1 = 0ll;
        if(num(a[i]) + num(b[i]) == num(c[i])) {
            ans += s00 + 1ll;
            s0 = s00 + 1ll;
        }
        else if(num(a[i]) + num(b[i]) + 1 == num(c[i])) {
            ans += s11;
            s0 = s11;
        }
        else if(num(a[i]) + num(b[i]) == num(c[i]) + 10)
            s1 = s00 + 1ll;
        else if(num(a[i]) + num(b[i]) + 1 == num(c[i]) + 10)
            s1 = s11;
    }
    cout << ans << "\n";
    return 0;
}