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

int a, b, c;
void fun(int carry, vector<LL> &ok1, vector<LL> &ok2, vector<LL> &ok, int idx) {
    int sum = a + b + carry;
    if (sum % 10 == c) {
        int to_l = sum / 10;
        if (to_l == 0) ok[idx] = ok1[idx + 1] + 1;
        else ok[idx] = ok2[idx + 1];
    } else {
        ok[idx] = 0;
    }
}

int main() {
    ios_base::sync_with_stdio(0);cin.tie(0);
    string A, B, C;
    cin >> A >> B >> C;
    int n = A.size();
    vector<LL> ok1(n + 2, 0), ok2(n + 2, 0);
    
    for (int i = n - 1; i >= 0; i--) {
        a = A[i] - '0';b = B[i] - '0';c = C[i] - '0';
        fun(0, ok1, ok2, ok1, i); 
        fun(1, ok1, ok2, ok2, i); 
    }

    LL res = 0;
    for (int i = 0; i < n; i++) res += ok1[i];

    cout << res << '\n';
}