#include <bits/stdc++.h>
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define drep(i,j,n) for(int i=0;i<(int)(n-1);i++)for(int j=i+1;j<(int)(n);j++)
#define trep(i,j,k,n) for(int i=0;i<(int)(n-2);i++)for(int j=i+1;j<(int)(n-1);j++)for(int k=j+1;k<(int)(n);k++)
#define codefor int test;scanf("%d",&test);while(test--)
#define INT(...) int __VA_ARGS__;in(__VA_ARGS__)
#define LL(...) ll __VA_ARGS__;in(__VA_ARGS__)
#define yes(ans) if(ans)printf("yes\n");else printf("no\n")
#define Yes(ans) if(ans)printf("Yes\n");else printf("No\n")
#define YES(ans) if(ans)printf("YES\n");else printf("NO\n")
#define vector1d(type,name,...) vector<type>name(__VA_ARGS__)
#define vector2d(type,name,h,...) vector<vector<type>>name(h,vector<type>(__VA_ARGS__))
#define vector3d(type,name,h,w,...) vector<vector<vector<type>>>name(h,vector<vector<type>>(w,vector<type>(__VA_ARGS__)))
#define umap unordered_map
#define uset unordered_set
using namespace std;
using ll = long long;
const int MOD=1000000007;
const int MOD2=998244353;
const int INF=1<<30;
const ll INF2=(ll)1<<60;
//入力系
void scan(int& a){scanf("%d",&a);}
void scan(long long& a){scanf("%lld",&a);}
template<class T,class L>void scan(pair<T, L>& p){scan(p.first);scan(p.second);}
template<class T> void scan(T& a){cin>>a;}
template<class T> void scan(vector<T>& vec){for(auto&& it:vec)scan(it);}
void in(){}
template <class Head, class... Tail> void in(Head& head, Tail&... tail){scan(head);in(tail...);}
//出力系
void print(const int& a){printf("%d",a);}
void print(const long long& a){printf("%lld",a);}
void print(const double& a){printf("%.15lf",a);}
template<class T,class L>void print(const pair<T, L>& p){print(p.first);putchar(' ');print(p.second);}
template<class T> void print(const T& a){cout<<a;}
template<class T> void print(const vector<T>& vec){if(vec.empty())return;print(vec[0]);for(auto it=vec.begin();++it!= vec.end();){putchar(' ');print(*it);}}
void out(){putchar('\n');}
template<class T> void out(const T& t){print(t);putchar('\n');}
template <class Head, class... Tail> void out(const Head& head,const Tail&... tail){print(head);putchar(' ');out(tail...);}
//デバッグ系
template<class T> void dprint(const T& a){cerr<<a;}
template<class T> void dprint(const vector<T>& vec){if(vec.empty())return;cerr<<vec[0];for(auto it=vec.begin();++it!= vec.end();){cerr<<" "<<*it;}}
void debug(){cerr<<endl;}
template<class T> void debug(const T& t){dprint(t);cerr<<endl;}
template <class Head, class... Tail> void debug(const Head& head, const Tail&... tail){dprint(head);cerr<<" ";debug(tail...);}
ll intpow(ll a, ll b){ ll ans = 1; while(b){ if(b & 1) ans *= a; a *= a; b /= 2; } return ans; }
ll modpow(ll a, ll b, ll p){ ll ans = 1; while(b){ if(b & 1) (ans *= a) %= p; (a *= a) %= p; b /= 2; } return ans; }
ll updivide(ll a,ll b){if(a%b==0) return a/b;else return (a/b)+1;}
template<class T> void chmax(T &a,const T b){if(b>a)a=b;}
template<class T> void chmin(T &a,const T b){if(b<a)a=b;}
 
int main(){
    LL(n,t);
    vector<ll> a(n),suma(1,0),sumb(1,0);
    in(a);
    int pre;
    for(int i=0;i<n/2;i++){
        pre=suma.size();
        for(int j=0;j<pre;j++){
            if(suma[j]+a[i]<=t)suma.emplace_back(suma[j]+a[i]);
        }
    }
    for(int i=n/2;i<n;i++){
        pre=sumb.size();
        for(int j=0;j<pre;j++){
            if(sumb[j]+a[i]<=t)sumb.emplace_back(sumb[j]+a[i]);
        }
    }
    sort(all(suma));
    sort(all(sumb));
    ll ans=0,d,bt,bi=sumb.size()-1;
    for(int i=0;i<suma.size();i++){
        bt=t-suma[i];
        while(sumb[bi]>bt)bi--;
        chmax(ans,suma[i]+sumb[bi]);
    }
    out(ans);
}
//g++  7.4.0

#include <iostream>
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define MAXN 200005
vector<ll> adj[MAXN];
ll vis[MAXN];
ll dp[MAXN];
ll A[MAXN];

void DFS(ll s)
{
    vis[s] = 1;
    
    for(auto it: adj[s])
    {
        ll v = it;
        if(!vis[v])
            DFS(v);
        
        ll val = max(A[v],dp[v]);
        dp[s] = max(dp[s],val);
    }
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    
    ll N,M; cin>>N>>M;
    
    for(ll i=0;i<N;++i)
        cin>>A[i + 1];
    
    for(ll i=0;i<M;++i)
    {
        ll u,v; cin>>u>>v;
        adj[u].push_back(v);
    }
    
    for(ll i=1;i<=N;++i)
    {
        if(!vis[i])
            DFS(i);
    }
    
    ll ans = LLONG_MIN;
    
    for(ll i=1;i<=N;++i)
    {
        if(adj[i].size()) //Not a leaf
        {
            ans = max(ans,dp[i] - A[i]);
        }
    }
    
    cout<<ans<<endl;
}