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#include <bits/stdc++.h>

// hashing ? prolly hard

using int64_t = int64_t;

template <typename T> 
struct FenwickTree{
	// 0 indexed
	// easily can be modified
	// to answer add range query point.
	#define lsb(x) ((x) & (-x))
	const bool zero_indexed = true;
	int n;
	std::vector<T> tab;
	
	FenwickTree () {}
	FenwickTree (int _n) : n(_n) {
		tab.assign(n + 1, T());
	}
	
	void dodaj(int pos, T val) {
		if(zero_indexed) pos = pos + 1;
		while(pos <= n){
			tab[pos] += val;
			pos += lsb(pos);
		}
	}
	
	// uwaga z ustaw + range updates
	void ustaw(int pos, T val) {
		T at_now = suma(pos, pos);
		dodaj(pos, -at_now + val);
	}
	
	void ustaw2(int pos, T val){
		T at_now = suma(pos);
		dodaj(pos, -at_now + val);
		dodaj(pos+1, -(-at_now + val));
	}
	
	T suma(int pos) {
		if(zero_indexed) pos = pos + 1;
		T res = T();
		while(pos > 0){
			res += tab[pos];
			pos -= lsb(pos);
		}
		return res;
	}
	
	T suma(int l, int r){
		return suma(r) - (l >= 1 ? suma(l - 1) : T());
	}
};

int main(){
	using namespace std;
	ios::sync_with_stdio(false), cin.tie(nullptr);
	
	string a, b, c;
	cin >> a >> b >> c;
	
	int n = (int)a.size();
	assert(n == (int)b.size());
	assert(n == (int)c.size());
	
	vector<vector<int>> dig(n, vector<int> (3));
	
	vector<int> f(n);
	for(int i = 0;i < n;i++){
		dig[i][0] = (a[i] - '0');
		dig[i][1] = (b[i] - '0');
		dig[i][2] = (c[i] - '0');
		if((dig[i][0] + dig[i][1]) % 10 == dig[i][2]){
			f[i] = 1;
		} else if((dig[i][0] + dig[i][1] + 1) % 10 == dig[i][2]){
			f[i] = 2;
		} else {
			f[i] = 3; // BAD!
		}
	}
	
	vector<vector<int>> g(n, vector<int> (2, n));
	// leftmost digit such that the sum is okay 
	// n if its never okay
	
	if(f[0] == 1) g[0][0] = 0;
	if(f[0] == 2) g[0][1] = 0;
	
	for(int i = 1;i < n;i++){
		// Case #1: we don't propagate 1 from the right
		if(dig[i][0] + dig[i][1] < 10){
			if(f[i] == 1){
				g[i][0] = i;
				g[i][0] = min(g[i][0], g[i - 1][0]);
			}
			// f[i] = 2 => nie da się bo nie dostaje 
		} else {
			if(f[i] == 1){
				g[i][0] = i;
				g[i][0] = min(g[i][0], g[i - 1][1]);
			}
		}
		
		// Case #2: we propagate a 1 from the right
		if(dig[i][0] + dig[i][1] + 1 < 10){
			if(f[i] == 2){
				g[i][1] = i;
				g[i][1] = min(g[i][1], g[i - 1][0]);
			}
		} else {
			if(f[i] == 2){
				g[i][1] = i;
				g[i][1] = min(g[i][1], g[i - 1][1]);
			}
		}
	}
	
	vector<int> normal(n);
	for(int i = 0;i < n;i++){
		if(dig[i][0] + dig[i][1] < 10){
			normal[i] = 1;
		}
	}

	int64_t ans = 0;
	//~ for(int i = 0;i < n;i++){
		//~ std::cerr << " i = " << i << " g[i][0]: " << g[i][0] << " g[i][1]: " << g[i][1] << std::endl;
		//~ int64_t add = max(int64_t(0), i - g[i][0] + int64_t(1));
		//~ ans += add;
		//~ if(g[i][0] == n) continue;
		//~ int left = g[i][0];
		//~ // okay but we need to exclude the ones that propagate one because 
		//~ // we cannot end with them.
		//~ std::cerr << " >> getNormal(left, i): " << getNormal(left, i) << std::endl;
		
		//~ ans += getNormal(left, i);
	//~ }
	
	FenwickTree<int64_t> fen(n + 2);
	//~ for(int i = 0;i < n;i++){
		//~ // okay i am the last one
		//~ if(!normal[i] || f[i] == 3) continue;
		//~ if(dig[i][0] + dig[i][1] + 1 == 10 && f[i] == 2) continue;
		//~ // count the number of g[j][0] such that g[j][0] <= i
		//~ for(int j = i;j < n;j++){
			//~ if(g[j][0] <= i){
				//~ ans += 1;
			//~ }
		//~ }
	//~ }
	
	// speedup
	for(int i = n-1;i >= 0;i--){
		fen.dodaj(g[i][0], 1);
		if(!normal[i] || f[i] == 3) continue;
		if(dig[i][0] + dig[i][1] + 1 == 10 && f[i] == 2) continue;
		ans += fen.suma(0,i);
	}
	
	cout << ans << '\n';

	return 0;
}

/*

445195
646335
234530

*/