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

int main () {
  ios_base::sync_with_stdio(0); cin.tie(0);
  string a, b, c;
  cin >> a >> b >> c;
  int64_t ans = 0;
  int z0 = 0, z1 = 0;
  for (int i = (int)a.size()-1; i >= 0; i--) {
    int da = a[i] - '0';
    int db = b[i] - '0';
    int dc = c[i] - '0';
    z0 += 1;
    int nz0 = 0, nz1 = 0;
    for (int k: {0, 1}) {
      if (da+db+k == dc) nz0 += (k ? z1 : z0);
      if (da+db+k == dc+10) nz1 += (k ? z1 : z0);
    }
    z0 = nz0;
    z1 = nz1;
    ans += z0;
  }
  cout << ans << '\n';
}