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

int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    string A, B, C;
    cin >> A >> B >> C;
    int n = A.size();
    vector<int> carry(n + 1, 0);
    vector<bool> good(n, false);
    for (int i = n - 1; i >= 0; i--) {
        int a = A[i] - '0';
        int b = B[i] - '0';
        int c = C[i] - '0';
        int sum = a + b + carry[i + 1];
        if (sum % 10 == c) {
            good[i] = true;
        }
        carry[i] = sum / 10;
    }
    long long result = 0;
    int i = 0;
    while (i < n) {
        if (!good[i]) {
            i++;
            continue;
        }
        int j = i;
        while (j < n && good[j]) j++;
        int len = j - i;
        int start = i;
        for (int k = i; k < j; k++) {
            if (carry[k] == 0) {
                int end = j - 1;
                result += (end - k + 1);
            }
        }
        i = j;
    }
    cout << result << "\n";
}