#include <bits/stdc++.h>
#define syosu(x) fixed<<setprecision(x)
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> P;
typedef pair<double,double> pdd;
typedef pair<ll,ll> pll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<double> vd;
typedef vector<vd> vvd;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<string> vs;
typedef vector<P> vp;
typedef vector<vp> vvp;
typedef vector<pll> vpll;
typedef pair<P,int> pip;
typedef vector<pip> vip;
const int inf=1<<30;
const ll INF=1ll<<60;
const double pi=acos(-1);
const double eps=1e-8;
const ll mod=1e9+7;
const int dx[4]={-1,0,1,0},dy[4]={0,-1,0,1};

int n,m,c;
vi a;

int main(){
	cin>>n>>m>>c;
	a=vi(c);
	for(int i=0;i<c;i++) cin>>a[i];
	priority_queue<P> q;
	for(int i=0;i<n;i++){
		int A,B;
		cin>>A>>B;
		q.push({B,A-1});
	}
	int t=0,res=0;
	while(t<m&&q.size()){
		P p=q.top();
		q.pop();
		int A=p.first,B=p.second;
		if(a[B]){
			a[B]--;
			res+=A;
			t++;
		}
	}
	cout<<res<<endl;
}
