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#include <bits/stdc++.h>

#define ALL(x) (x).begin(), (x).end()
#define SZ(x) ((int)(x).size())

using namespace std;

#ifdef LOCAL
template<typename A, typename B>
auto&operator<<(auto&o,pair<A, B>p){return o<<"("<<p.first<<", "<<p.second<<")";}
auto operator<<(auto&o,auto x)->decltype(x.end(),o){o<<"{";int i=0;for(auto e:x)o<<&","[!i++]<<e;return o<<"}";}
#define debug(X...)cerr<<"["#X"]: ",[](auto...$){((cerr<<$<<"; "),...)<<endl;}(X)
#else
#define debug(...){}
#endif

using i64 = long long;
using ll = long long;
using pii = pair<int, int>;
using pll = pair<i64, i64>;
using vi = vector<int>;
using vll = vector<i64>;

// Some large prime found on wikipedia :D
const i64 MOD = 418'032'645'936'712'127LL;

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cout << fixed << setprecision(14);
	cerr << fixed << setprecision(6);

	int n;
	string A, B, C;
	cin >> A >> B >> C;
	n = SZ(A);

	map<i64, int> rems;

	i64 cur_rem = 0;
	i64 cur_digit = 1;
	++rems[cur_rem];
	i64 ans = 0;

	for (int i = n - 1; i >= 0; --i) {
		const int d = (A[i] - '0') + (B[i] - '0') - (C[i] - '0');
		cur_rem = (cur_rem + cur_digit * d) % MOD;
		if (cur_rem < 0) {
			cur_rem += MOD;
		}

		ans += rems[cur_rem];
		++rems[cur_rem];
		cur_digit = (cur_digit * 10) % MOD;
	}

	cout << ans << "\n";
}