import std.array, std.stdio, std.string, std.algorithm, std.conv;

int[][] dp;

void main()
{
    int N = readln.strip.to!int;
    int C = readln.strip.to!int;
    int V = readln.strip.to!int;
    auto S = readln.split.map!"(a.to!int - 1)";
    auto T = readln.split.map!"(a.to!int - 1)";
    auto Y = readln.split.map!(to!int);
    auto M = readln.split.map!(to!int);

    int[] es;
    es.length = N;
    foreach (ref e; es) {
        e = 0;
    }
    int[][] edge;
    edge.length = N;
    foreach (ref e; edge) {
        e.length = V;
    }
    int[][] dist;
    dist.length = N;
    foreach (ref e; dist) {
        e.length = V;
    }
    int[][] cost;
    cost.length = N;
    foreach (ref e; cost) {
        e.length = V;
    }

    foreach (i; 0..V) {
        edge[S[i]][es[S[i]]] = T[i];
        dist[S[i]][es[S[i]]] = M[i];
        cost[S[i]][es[S[i]]] = Y[i];
        es[S[i]]++;
    }

    dp.length = N;
    foreach (ref d; dp) {
        d.length = C+1;
        d[] = int.max;
    }
    foreach(ref d; dp[0]) d = 0;

    foreach (n; 0..N) {
        foreach (c; 0..C+1) {
            if (dp[n][c] != int.max)
                foreach (j; 0..es[n]) {
                    if (c + cost[n][j] <= C) dp[edge[n][j]][c + cost[n][j]] = min(dp[edge[n][j]][c+cost[n][j]], dp[n][c] + dist[n][j]);
                }
        }
    }
    if (dp[N-1][C] == int.max) writeln(-1);
    else writeln(dp[N-1][C]);
}