#include <bits/stdc++.h>
using namespace std;
struct Edge {
  int from, to, capacity, cost;
};
vector<vector<int>> adj, cost, capacity;
const int INF = 1e9;
void shortest_paths(int n, int v0, vector<int>& d, vector<int>& p) {
  d.assign(n, INF);
  d[v0] = 0;
  vector<bool> inq(n, false);
  queue<int> q;
  q.push(v0);
  p.assign(n, -1);
  while (!q.empty()) {
    int u = q.front();
    q.pop();
    inq[u] = false;
    for (int v : adj[u]) {
      if (capacity[u][v] > 0 && d[v] > d[u] + cost[u][v]) {
        d[v] = d[u] + cost[u][v];
        p[v] = u;
        if (!inq[v]) {
          inq[v] = true;
          q.push(v);
        }
      }
    }
  }
}
int min_cost_flow(int N, vector<Edge> edges, int K, int s, int t, int& maxf) {
  adj.assign(N, vector<int>());
  cost.assign(N, vector<int>(N, 0));
  capacity.assign(N, vector<int>(N, 0));
  for (Edge e : edges) {
    adj[e.from].push_back(e.to);
    adj[e.to].push_back(e.from);
    cost[e.from][e.to] = e.cost;
    cost[e.to][e.from] = -e.cost;
    capacity[e.from][e.to] = e.capacity;
  }
  int flow = 0;
  int cost = 0;
  vector<int> d, p;
  while (flow < K) {
    shortest_paths(N, s, d, p);
    if (d[t] == INF) break;
    int f = K - flow;
    int cur = t;
    while (cur != s) {
      f = min(f, capacity[p[cur]][cur]);
      cur = p[cur];
    }
    flow += f;
    cost += f * d[t];
    cur = t;
    while (cur != s) {
      capacity[p[cur]][cur] -= f;
      capacity[cur][p[cur]] += f;
      cur = p[cur];
    }
  }
  maxf = flow;
  return cost;
}
const int MAXE = 10000;
int n;
int last;
int src, dest;
string s, t;
vector<Edge> edges;
void addE(int a, int b, int ca, int co) {
  Edge e;
  e.from = a;
  e.to = b;
  e.capacity = ca;
  e.cost = co;
  edges.push_back(e);
}
void create_edges(int w, int f[], int a) {
  for (int i = 0; i < 26; i++) addE(last, w * 26 + i, f[i], 0);
  addE(src, last, a, w + 1);
  last++;
}
void freq(string s, int f[]) {
  fill(f, f + 26, 0);
  for (char c : s) f[c - 'a']++;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cin >> t;
  int a;
  int f[26];
  int base;
  cin >> n;
  last = 26 * n;
  src = 26 * n + n + 26;
  dest = src + 1;
  for (int i = 0; i < n; i++) {
    cin >> s;
    cin >> a;
    freq(s, f);
    create_edges(i, f, a);
  }
  freq(t, f);
  for (int i = 0; i < 26; i++) {
    for (int w = 0; w < n; w++) addE(w * 26 + i, last, 200, 0);
    addE(last, dest, f[i], 0);
    last++;
  }
  int maxf;
  int co = min_cost_flow(dest + 1, edges, 10000, src, dest, maxf);
  if (maxf < t.length())
    cout << -1 << endl;
  else
    cout << co << endl;
  return 0;
}
