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

typedef long long int lld;
#define all(m) m.begin(),m.end()
#define sz(m) lld(m.size())
#define pb push_back
#define mod 1000000007
#define st first
#define nd second
#define endl "\n"

void swagWaalaFunction()
{
	lld a,b,c,ans=0;
	cin>>a>>b>>c;

	ans=21-a-b-c;
	cout<<ans<<endl;
}

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

	lld tc=1;
	//cin>>tc;

	for(int i=0;i<tc;i++)
	{
		// cout<<"Case #"<<i+1<<": ";
		swagWaalaFunction();
	}
	return 0;
}
#pragma GCC optimize("Ofast")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,fma")
#pragma GCC optimize("unroll-loops")
#include <bits/stdc++.h> 
 
using namespace std;
 
typedef long long ll;
typedef long double ld;
typedef pair<int,int> p32;
typedef pair<ll,ll> p64;
typedef pair<double,double> pdd;
typedef vector<ll> v64;
typedef vector<int> v32;
typedef vector<vector<int> > vv32;
typedef vector<vector<ll> > vv64;
typedef vector<vector<p64> > vvp64;
typedef vector<p64> vp64;
typedef vector<p32> vp32;
ll MOD = 998244353;
ll mod = 1000000007;
double eps = 1e-12;
#define forn(i,e) for(ll i = 0; i < e; i++)
#define forsn(i,s,e) for(ll i = s; i < e; i++)
#define rforn(i,s) for(ll i = s; i >= 0; i--)
#define rforsn(i,s,e) for(ll i = s; i >= e; i--)
#define ln "\n"
#define dbg(x) cout<<#x<<" = "<<x<<ln
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define INF 2e18
#define fast_cin() ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL)
#define all(x) (x).begin(), (x).end()
#define sz(x) ((ll)(x).size())
 

void solve()
{
    int a,b,c;
    cin>>a>>b>>c;
    cout<<21-(a+b+c);
}
int main()
{
    solve();
}