#include <stdio.h>
#include <atcoder/all>
#include <bits/stdc++.h>
using namespace std;
using namespace atcoder;
using mint = modint998244353;
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define Inf32 1000000001
#define Inf64 4000000000000000001
#define sq 1300


int main(){
	
	int n,m,c;
	cin>>n>>m>>c;
	mcf_graph<long long,long long> G(n+1);
	long long ans = 0;
	rep(i,n){
		int a;
		cin>>a;
		ans += a;
		G.add_edge(i,i+1,1,a);
		G.add_edge(i+1,i,1,a);
	}
	
	rep(i,m){
		int l,r;
		cin>>l>>r;
		l--;
		G.add_edge(l,r,1,c);
		G.add_edge(r,l,1,c);
	}
	ans -= G.flow(0,n,1).second;
	//ans *= -1;
	
	cout<<ans<<endl;
	return 0;
}