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#include <iostream>
#include <string>
#include <vector>


int main() {
    std::string s1, s2, s3;
    std::cin >> s1 >> s2 >> s3;
    int n = s1.size();
    long long result = 0;
    
    long long mod0 = 0;
    long long mod1 = 0;

    for (int i = n - 1; i >= 0; i--) {
        int a = s1[i] - '0';
        int b = s2[i] - '0';
        int c = s3[i] - '0';

        long long next_mod0 = 0;
        long long next_mod1 = 0;

        if (a + b == c) {
            next_mod0 = mod0 + 1; 
            next_mod1 = 0;
        } 
        else if (a + b == c + 10) {
            next_mod0 = 0;
            next_mod1 = mod0 + 1;
        } 
        else if (a + b + 1 == c) {
            next_mod0 = mod1;
            next_mod1 = 0;
        } 
        else if (a + b == c + 9) {
            next_mod0 = 0;
            next_mod1 = mod1;
        } 
        else {
            next_mod0 = 0;
            next_mod1 = 0;
        }

        mod0 = next_mod0;
        mod1 = next_mod1;

        result += mod0;
    }

    std::cout << result;
}