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#include <bits/stdc++.h>

using namespace std;

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    string a,b, c;
    cin >> a >> b >> c;
    long long n = a.size(), ans = 0;

    vector<int> np(n + 1);
    vector<int> yp(n + 1);

    for(int i = n-1; i >= 0; --i) {
        if ((a[i] - '0') + (b[i] - '0') == (c[i] - '0')) {
            np[i] = 1; 
        }
        else if ((a[i] - '0') + (b[i] - '0') == (c[i] - '0') + 10) {
            yp[i] = 1;
        }

        if ((a[i] - '0') + (b[i] - '0') == (c[i] - '0')) {
            np[i] += np[i+1];
        }
        else if ((a[i] - '0') + (b[i] - '0') == (c[i] - '0') + 10) {
            yp[i] += np[i+1];
        }

        if ((a[i] - '0') + (b[i] - '0') + 1 == (c[i] - '0')) {
            np[i] += yp[i+1];
        }
        else if ((a[i] - '0') + (b[i] - '0') + 1 == (c[i] - '0') + 10) {
            yp[i] += yp[i+1];
        }

        ans += np[i];
    }

    cout << ans;

    return 0;
}