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

using namespace std;

#define int long long

signed main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    string a, b, c;
    cin>>a>>b>>c;

    int n = a.size();
    int ans = 0;
    
    int dp[2] = {0, 0};

    for(int i = n - 1; i >= 0; i--){
        int val_a = a[i] - '0';
        int val_b = b[i] - '0';
        int val_c = c[i] - '0';
        int przej[2] = {-1, -1};
        for(int j = 0; 2>j; j++){
            int sum = val_a + val_b + j;
            if(sum % 10 == val_c) przej[j] = sum / 10;
        }
        int new_dp[2] = {0, 0};
        if(przej[0] != -1) new_dp[przej[0]] += 1;

        for(int j = 0; 2>j; j++){
            if(przej[j] != -1) new_dp[przej[j]] += dp[j];
        }
        dp[0] = new_dp[0];
        dp[1] = new_dp[1];
        ans += dp[0];
    }
    cout<<ans;
}