#include <bits/stdc++.h> 
using namespace std;  
#define ll   long long int
#define INF 1000000007

int main()
{
	string s1,s2,s3;
	cin>>s1>>s2>>s3;
	ll a = 0,b = 0,c = 0;
	string ch = "a";
	while(1)
	{
		if(ch == "a")
		{
			if(s1.size()>a)
			{
				ch = s1[a];
				a++;
			}
			else
			{
				cout<<"A"<<endl;
				return 0;
			}
		}
				if(ch == "b")
		{
			if(s2.size()>b)
			{
				ch = s2[b];
				b++;
			}
			else
			{
				cout<<"B"<<endl;
				return 0;
			}
		}
				if(ch == "c")
		{
			if(s3.size()>c)
			{
				ch = s3[c];
				c++;
			}
			else
			{
				cout<<"C"<<endl;
				return 0;
			}
		}
	}
}

#pragma GCC optimize("Ofast")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx")
#pragma GCC optimize("unroll-loops")
//#pragma warning(disable : 4996)

//#include"atcoder/all"


#ifdef _MSC_VER
#include <intrin.h>

#define __builtin_popcount __popcnt
#define __builtin_popcountll __popcnt64
#endif

#include <limits.h>
#include <math.h>
#include <time.h>

#include <algorithm>
#include <array>
#include <bitset>
#include <cassert>
#include <complex>
#include <cstdio>
#include <cstring>
#include <functional>
#include <iomanip>
#include <iostream>
#include <iterator>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <vector>

using namespace std;
//using namespace atcoder;

#define REP(i, n) for (int i = 0; i < (n); ++i)
#define REPR(i, n) for (int i = n - 1; i >= 0; --i)
#define FOR(i, m, n) for (int i = m; i < n; ++i)
#define FORR(i, m, n) for (int i = m - 1; i >= n; --i)
#define SORT(v, n) sort(v, v + n);
#define VSORT(v) sort(v.begin(), v.end());
#define REVERSE(v, n) reverse(v, v + n);
#define VREVERSE(v) reverse(v.begin(), v.end())
#define ll long long
#define print(x) cout << (x) << endl
#define pe(x) cout << (x) << " "
#define DEBUG(x) cout << #x << ": " << x << endl
#define lb(v, n) lower_bound(v.begin(), v.end(), (n))
#define ub(v, n) upper_bound(v.begin(), v.end(), (n))
#define int long long
//#define double long double
#define all(x) (x).begin(), (x).end()
#define print_space(v) REP(i, v.size()) cout << v[i] << " \n"[i==(int)v.size()-1]
template <typename T1, typename T2> inline void chmin(T1& a, T2 b) { if (a > b) a = b; }
template <typename T1, typename T2> inline void chmax(T1& a, T2 b) { if (a < b) a = b; }
typedef pair<int, int> pii;
typedef pair<long long, long long> pll;
std::random_device rd;
std::mt19937 mt(rd());
constexpr ll MOD = 1e9 + 7;
constexpr int MAX = 500050;
const double pi = acos(-1);
constexpr double EPS = 1e-8;
constexpr ll LINF = 1e18 + 1;
constexpr int INF = 1e9 + 1;


void solve() {
	int A, B, C, D; cin >> A >> B >> C >> D;
	int K; cin >> K;
	int t1 = A * 60 + B;
	int t2 = C * 60 + D;
	int d = t2 - t1;
	print(d - K);
}



signed main() {
	cin.tie(0);
	ios::sync_with_stdio(false);

	//int q;
	//cin >> q;
	//while (q--)
	solve();

}
