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

#define REP(i,n) for(int (i)=0;(i)<(int)(n);++(i))

int S[1555];
int T[1555];
int Y[1555];
int M[1555];

const int INF = (int)1e9;
int best[55][310];

void updmin(int& u, int x) {
	if (u > x) u = x;
}

int main() {
	int N, C, E;
	cin >> N >> C >> E;
	for (int e = 0; e < E; e++) cin >> S[e];
	for (int e = 0; e < E; e++) cin >> T[e];
	for (int e = 0; e < E; e++) cin >> Y[e];
	for (int e = 0; e < E; e++) cin >> M[e];

	vector<pair<int, int>> es;
	for (int i = 0; i < E; i++) {
		es.push_back(make_pair(S[i], i));
	}
	sort(es.begin(), es.end());

	for (int i = 0; i < 55; i++) for (int j = 0; j < 310; j++) best[i][j] = INF;
	best[1][0] = 0;
	for (int step = 0; step < 2; step++) {
		for (int i = 0; i < E; i++) {
			int e = es[i].second;
			for (int c = 0; c + Y[e] <= C; c++) {
				updmin(best[T[e]][c + Y[e]], best[S[e]][c] + M[e]);
			}
		}
	}

	int ans = INF;
	for (int c = 0; c <= C; c++) updmin(ans, best[N][c]);
	if (ans >= INF / 2) ans = -1;
	cout << ans << endl;
}