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

int q_max(int a,int b,int c,int d){ a=a>b?c:d; a=a>c?a:c; a=a>d?a:d; return a; }

int main(){ int a,b,c,d; cin >>a>>b>>c>>d;

int M_max=q_max(a,b,c,d);
cout <<M_max;

return 0;

}

#include<iostream>
using namespace std;
int main()
{
	int x,y,z,n;
	cin>>x>>y>>z>>n;
	if(x>=y&&x>=z&&x>=n)
	  cout<<x;
	if(y>=z&&y>=x&&y>=n)
 	  cout<<y;
	if(z>=x&&z>=y&&z>=n)
	  cout<<z;
	if(n>=x&&n>=y&&n>=z)
	  cout<<n;
	return 0;
}

#include<bits/stdc++.h> using namespace std; int main() { int x,ma=0; for(int i=1;i<=4;i++){ cin>>x; if(x>ma){ ma=x; } } cout <<ma<<endl; return 0; }

#include<bits/stdc++.h> using namespace std; int main() { int a,b,c,d; cin>>a>>b>>c>>d; if(a>b&&a>c&&a>d) cout<<a; if(b>a&&b>c&&b>d) cout<<b; if(c>a&&c>b&&c>d) cout<<c; if(d>a&&d>b&&d>c) cout<<d; return 0; }

#include <bits/stdc++.h>
const int N = 100005;
int rt,tot,fa[N],ch[N][2],val[N],cnt[N],sz[N];
struct Splay {
	void maintain(int x){
		sz[x]=sz[ch[x][0]]+sz[ch[x][1]]+cnt[x];
	}
	bool get(int x){
		return x==ch[fa[x]][1];
	}
	void clear(int x){
		ch[x][0]=ch[x][1]=fa[x]=val[x]=sz[x]=cnt[x]=0;
	}
	void rotate(int x){
		int y=fa[x],z=fa[y],chk=get(x);
		ch[y][chk]=ch[x][chk^1];
		if(ch[x][chk^1])fa[ch[x][chk^1]]=y;
		ch[x][chk^1]=y;
		fa[y]=x;
		fa[x]=z;
		if(z)ch[z][y==ch[z][1]]=x;
		maintain(y);
		maintain(x);
	}
	void splay(int x){
		for (int f=fa[x];f=fa[x],f;rotate(x)){
			if(fa[f])rotate(get(x)==get(f)?f:x);
		}
		rt=x;
	}
	void ins(int k){
		if(!rt){
			val[++tot]=k;
			cnt[tot]++;
			rt=tot;
			maintain(rt);
			return;
		}
		int cur=rt,f=0;
		while(1){
			if(val[cur]==k){
				cnt[cur]++;
				maintain(cur);
				maintain(f);
				splay(cur);
				break;
			}
			f=cur;
			cur=ch[cur][val[cur]<k];
			if(!cur){
				val[++tot]=k;
				cnt[tot]++;
				fa[tot]=f;
				ch[f][val[f]<k]=tot;
				maintain(tot);
				maintain(f);
				splay(tot);
				break;
			}
		}
	}
	int rk(int k){
		int res=0,cur=rt;
		while(1){
			if(k<val[cur]){
				cur = ch[cur][0];
			}
			else{
				res+=sz[ch[cur][0]];
				if(k==val[cur]){
					splay(cur);
					return res + 1;
				}
				res+=cnt[cur];
				cur=ch[cur][1];
			}
		}
	}
	int kth(int k){
		int cur=rt;
		while(1){
			if(ch[cur][0]&&k<=sz[ch[cur][0]]){
				cur=ch[cur][0];
			}
			else{
				k-=cnt[cur]+sz[ch[cur][0]];
				if(k<=0){
					splay(cur);
					return val[cur];
				}
				cur = ch[cur][1];
			}
		}
	}
	int pre(){
		int cur=ch[rt][0];
		if(!cur)return cur;
		while(ch[cur][1])cur=ch[cur][1];
		splay(cur);
		return cur;
	}
	int nxt(){
		int cur=ch[rt][1];
		if(!cur)return cur;
		while(ch[cur][0])cur=ch[cur][0];
		splay(cur);
		return cur;
	}
	void del(int k){
		rk(k);
		if(cnt[rt]>1){
			cnt[rt]--;
			maintain(rt);
			return;
		}
		if(!ch[rt][0]&&!ch[rt][1]){
			clear(rt);
			rt=0;
			return;
		}
		if(!ch[rt][0]){
			int cur=rt;
			rt=ch[rt][1];
			fa[rt]=0;
			clear(cur);
			return;
		}
		if(!ch[rt][1]){
			int cur=rt;
			rt=ch[rt][0];
			fa[rt]=0;
			clear(cur);
			return;
		}
		int cur=rt;
		int x=pre();
		fa[ch[cur][1]]=x;
		ch[x][1]=ch[cur][1];
		clear(cur);
		maintain(rt);
	}
}tree;
int main() {
	int a,b,c,d;
	std::cin>>a>>b>>c>>d;
	tree.ins(a);
	tree.ins(b);
	tree.ins(c);
	tree.ins(d);
	std::cout<<tree.kth(4);
	return 0;
}