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#include <iostream>
#include <string>
#include <vector>
#include <assert.h>

using int64 = long long int;

int64 solve(const std::string& a, const std::string& b, const std::string& c)
{
    int64 result = 0;
    bool need_1 = false;
    int num_exact_sums = 0;
    for (int i = 0; i < a.length(); ++i)
    {
        const int a_digit = a[i] - '0';
        const int b_digit = b[i] - '0';
        const int c_digit = c[i] - '0';
        const int ab_sum = a_digit + b_digit;
        if (ab_sum == c_digit)
        {
            if (need_1)
            {
                need_1 = false;
                num_exact_sums = 0;
            }
            ++num_exact_sums;
            result += num_exact_sums;
        }
        else if (ab_sum + 1 == c_digit)
        {
            if (need_1)
                num_exact_sums = 0;
            need_1 = true;
        }
        else if ((ab_sum + 1) % 10 == c_digit)
        {
            if (!need_1)
            {
                need_1 = false;
                num_exact_sums = 0;
            }
        }
        else if (ab_sum % 10 == c_digit)
        {
            if (!need_1)
            {
                num_exact_sums = 0;
            }
            else
            {
                ++num_exact_sums;
                result += num_exact_sums;
            }
            need_1 = false;
        }
        else
        {
            need_1 = false;
            num_exact_sums = 0;
        }
    }
    return result;
}

int64 num(const std::string& a, const int start, const int end)
{
    int64 value = 0;
    for (int i = start; i <= end; i++)
        value = value * 10 + (a[i] - '0');
    return value;
}

void check(const std::string& a, const std::string& b, const std::string& c, const int64 expected_result)
{
    int64 correct_result = 0;
    for (int start = 0; start < a.length(); ++start)
    for (int end = start; end < a.length(); ++end)
    {
        const int64 a_num = num(a, start, end);
        const int64 b_num = num(b, start, end);
        const int64 c_num = num(c, start, end);
        if (a_num + b_num == c_num)
            ++correct_result;
    }
    if (expected_result != correct_result)
    {
        std::cout << "ERROR: " << std::endl << a << std::endl << b << std::endl << c << std::endl;
        std::cout << "GOT: " << expected_result << std::endl;
        std::cout << "EXPECTED: " << correct_result << std::endl;
        assert(false);
    }
}

void test()
{
    std::string a, b, c;

#if 0
    a = b = c = "xxx";
    for (int a0 = 0; a0 <= 9; a0++)
    for (int a1 = 0; a1 <= 9; a1++)
    for (int a2 = 0; a2 <= 9; a2++)
    for (int b0 = 0; b0 <= 9; b0++)
    for (int b1 = 0; b1 <= 9; b1++)
    for (int b2 = 0; b2 <= 9; b2++)
    for (int c0 = 0; c0 <= 9; c0++)
    for (int c1 = 0; c1 <= 9; c1++)
    for (int c2 = 0; c2 <= 9; c2++)
    {
        a[0] = a0 + '0';
        a[1] = a1 + '0';
        a[2] = a2 + '0';
        b[0] = b0 + '0';
        b[1] = b1 + '0';
        b[2] = b2 + '0';
        c[0] = c0 + '0';
        c[1] = c1 + '0';
        c[2] = c2 + '0';
        int64 result = solve(a, b, c);
        check(a, b, c, result);
    }
#else
    const int tests = 1000 * 1000;
    const int n = 10;
    a.resize(n);
    b.resize(n);
    c.resize(n);
    for (int i = 0; i < tests; ++i)
    {
        for (int j = 0; j < n; ++j)
        {
            a[j] = '0' + (rand() % 10);
            b[j] = '0' + (rand() % 10);
            c[j] = '0' + (rand() % 10);
        }
        const int64 result = solve(a, b, c);
        check(a, b, c, result);
    }

#endif
}

int main()
{
    //test();

    std::string a, b, c;
    std::cin >> a >> b >> c;
    std::cout << solve(a, b, c);
    return 0;
}

/*

000
000
020

037523
040834
978367

11111
22222
33433

15015
25025
40040

0555
0445
1000

09
09
18

099
091
190

0111
0999
1000

*/