237_E. Build String
You desperately need to build some string t. For that you've got n more strings s1, s2, ..., sn. To build string t, you are allowed to perform exactly |t| (|t| is the length of string t) operations on these strings. Each operation looks like that:

  1. choose any non-empty string from strings s1, s2, ..., sn; 
  2. choose an arbitrary character from the chosen string and write it on a piece of paper; 
  3. remove the chosen character from the chosen string. 



Note that after you perform the described operation, the total number of characters in strings s1, s2, ..., sn decreases by 1. We are assumed to build string t, if the characters, written on the piece of paper, in the order of performed operations form string t.

There are other limitations, though. For each string si you know number ai — the maximum number of characters you are allowed to delete from string si. You also know that each operation that results in deleting a character from string si, costs i rubles. That is, an operation on string s1 is the cheapest (it costs 1 ruble), and the operation on string sn is the most expensive one (it costs n rubles).

Your task is to count the minimum amount of money (in rubles) you will need to build string t by the given rules. Consider the cost of building string t to be the sum of prices of the operations you use.

Input

The first line of the input contains string t — the string that you need to build.

The second line contains a single integer n (1 ≤ n ≤ 100) — the number of strings to which you are allowed to apply the described operation. Each of the next n lines contains a string and an integer. The i-th line contains space-separated string si and integer ai (0 ≤ ai ≤ 100). Number ai represents the maximum number of characters that can be deleted from string si.

All strings in the input only consist of lowercase English letters. All strings are non-empty. The lengths of all strings do not exceed 100 characters.

Output

Print a single number — the minimum money (in rubles) you need in order to build string t. If there is no solution, print -1.

Examples

Input

bbaze
3
bzb 2
aeb 3
ba 10


Output

8


Input

abacaba
4
aba 2
bcc 1
caa 2
bbb 5


Output

18


Input

xyz
4
axx 8
za 1
efg 4
t 1


Output

-1

Note

Notes to the samples:

In the first sample from the first string you should take characters "b" and "z" with price 1 ruble, from the second string characters "a", "e" и "b" with price 2 rubles. The price of the string t in this case is 2·1 + 3·2 = 8.

In the second sample from the first string you should take two characters "a" with price 1 ruble, from the second string character "c" with price 2 rubles, from the third string two characters "a" with price 3 rubles, from the fourth string two characters "b" with price 4 rubles. The price of the string t in this case is 2·1 + 1·2 + 2·3 + 2·4 = 18.

In the third sample the solution doesn't exist because there is no character "y" in given strings.
```python
class Edge:
    def __init__(self, to, cost, capacity, next_edge):
        self.to = to
        self.cost = cost
        self.origin_cost = cost
        self.capacity = capacity
        self.next_edge = next_edge
        self.pair = None


class MinCostMaxFlow:
    def __init__(self, max_node):
        self.null = Edge(0, 0, 0, None)
        self.max_node = max_node + 3
        self.total_cost = 0
        self.current_cost = 0
        self.visited = [False] * self.max_node
        self.arc_list = []
        self.edge_head = [self.null] * self.max_node
        self.source = max_node + 1
        self.sink = max_node + 2

    def AddArcWithCapacityAndUnitCost(self, start_node, end_node, capacity, cost):
        self.edge_head[start_node] = Edge(end_node, cost, capacity, self.edge_head[start_node])
        self.edge_head[end_node] = Edge(start_node, -cost, 0, self.edge_head[end_node])
        self.edge_head[start_node].pair = self.edge_head[end_node]
        self.edge_head[end_node].pair = self.edge_head[start_node]
        if start_node != self.source and start_node != self.sink and end_node != self.source and end_node != self.sink:
            self.arc_list.append(self.edge_head[end_node])

    def NumArcs(self):
        return len(self.arc_list)

    def Tail(self, index):
        return self.arc_list[index].to

    def Head(self, index):
        return self.arc_list[index].pair.to

    def UnitCost(self, index):
        return self.arc_list[index].pair.origin_cost

    def Flow(self, index):
        return self.arc_list[index].capacity

    def OptimalFlow(self):
        edge = self.edge_head[self.sink]
        total_flow = 0
        while id(edge) != id(self.null):
            total_flow += edge.capacity
            edge = edge.next_edge
        return total_flow

    def OptimalCost(self):
        return self.total_cost

    def SetNodeSupply(self, node, supply):
        if supply > 0:
            self.AddArcWithCapacityAndUnitCost(self.source, node, supply, 0)
        elif supply < 0:
            self.AddArcWithCapacityAndUnitCost(node, self.sink, -supply, 0)

    def aug(self, node_id, total_flow):
        if node_id == self.sink:
            self.total_cost += self.current_cost * total_flow
            return total_flow
        self.visited[node_id] = True
        flow = total_flow
        edge = self.edge_head[node_id]
        while id(edge) != id(self.null):
            if edge.capacity > 0 and edge.cost == 0 and not self.visited[edge.to]:
                delta = self.aug(edge.to, min(flow, edge.capacity))
                edge.capacity -= delta
                edge.pair.capacity += delta
                flow -= delta
                if flow == 0:
                    return total_flow
            edge = edge.next_edge
        return total_flow - flow

    def modify_label(self):
        min_cost = 1 << 63
        for node_id in range(0, self.max_node):
            if not self.visited[node_id]:
                continue
            edge = self.edge_head[node_id]
            while id(edge) != id(self.null):
                if edge.capacity > 0 and not self.visited[edge.to] and edge.cost < min_cost:
                    min_cost = edge.cost
                edge = edge.next_edge
        if min_cost == 1 << 63:
            return False
        for node_id in range(0, self.max_node):
            if not self.visited[node_id]:
                continue
            edge = self.edge_head[node_id]
            while id(edge) != id(self.null):
                edge.cost -= min_cost
                edge.pair.cost += min_cost
                edge = edge.next_edge
        self.current_cost += min_cost
        return True

    def Solve(self):
        while True:
            while True:
                self.visited = [False] * self.max_node
                if self.aug(self.source, 1 << 63) == 0:
                    break
            if not self.modify_label():
                break
        return self.total_cost


def main():
    s = input()
    n = int(input())
    source = 0
    sink = n + 26 + 1
    mcmf = MinCostMaxFlow(n + 28)
    length = len(s)
    num = [0] * 29
    for i in range(0, length):
        num[ord(s[i]) - ord('a') + 1] += 1
    for i in range(1, 27):
        if num[i] > 0:
            mcmf.AddArcWithCapacityAndUnitCost(i, sink, num[i], 0)
    for i in range(1, n + 1):
        s, used = input().split(' ')
        mcmf.AddArcWithCapacityAndUnitCost(source, 26 + i, int(used), 0)
        num = [0] * 29
        for j in range(0, len(s)):
            num[ord(s[j]) - ord('a') + 1] += 1
        for j in range(1, 27):
            if num[j] > 0:
                mcmf.AddArcWithCapacityAndUnitCost(26 + i, j, num[j], i)
    mcmf.SetNodeSupply(source, 1 << 63)
    mcmf.SetNodeSupply(sink, -(1 << 63))
    mcmf.Solve()
    if mcmf.OptimalFlow() != length:
        print("-1")
    else:
        print(mcmf.OptimalCost())


if __name__ == '__main__':
    main()

```