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#include <bits/stdc++.h>

using namespace std;
using ll = long long;

string nums[3];

const int nax = 1000 * 1000 + 10;

int carry[nax], need[nax], prefix_sum[nax], match[nax];

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

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int n;
    for (int i = 0; i < 3; ++i) {
        cin >> nums[i];
    }
    n = (int)nums[0].size();

    for (int i = 1; i <= n; ++i) {
        int sum = char_to_int(nums[0][i-1]) + char_to_int(nums[1][i-1]);
        if (sum >= 10) {
            carry[i] = 1;
        } else {
            carry[i] = 0;
        }

        if (char_to_int(nums[2][i-1]) == sum % 10) {
            need[i] = 0;
        } else if (char_to_int(nums[2][i-1]) == (sum + 1) % 10) {
            need[i] = 1;
        } else {
            need[i] = -1;
        }
    }

    prefix_sum[0] = 0;
    
    for (int i = 1; i <= n; ++i) {
        prefix_sum[i] = prefix_sum[i-1] + (carry[i] == 0);
    }

    ll answer = 0;

    int ptr = 2;

    for (int j = 1; j <= n; ++j) {
        // fix carry bit
        int consider = j;
        if (carry[j] == 1) {
            for (int i = j-1; i >= 1; --i) {
                int sum = char_to_int(nums[0][i-1]) + char_to_int(nums[1][i-1]);
                if (carry[i] == 0 && (sum + 1) >= 10) {
                    carry[i] = 1;
                    consider = i;
                } else {
                    break;
                }
            }
        }
        for (int i = consider; i <= j; ++i) {
            prefix_sum[i] = prefix_sum[i - 1] + (carry[i] == 0);
            if (i > 1 && need[i-1] == carry[i]) {
                match[i] = match[i-1] + 1;
            } else {
                match[i] = 0;
            }
        }
        if (need[j] == 0) {
            answer += prefix_sum[j] - prefix_sum[j - match[j] - 1];
        }
    }

    cout << answer << "\n";


    // for (int i = 1; i <= n; ++i) {
    //     cout << carry[i] << " ";
    // }
    // cout << "\n";
    // for (int i = 1; i <= n; ++i) {
    //     cout << need[i] << " ";
    // }
    // cout << "\n";

}