You are given a connected undirected graph with nodes and
edges, where each edge has a weight
and a value
. In one operation you can decrease the weight of some edge
by
, edge weights can be zero or negative. You are to perform at most
operations, and then choose some connected subgraph of the graph containing all
nodes (possibly the graph itself). Of all possible ways of doing so, you want to minimize the maximum edge weight of the connected subgraph.
Input Specification
The first line contains integers
,
, and
.
The next lines contain
integers
, indicating an undirected edge between
and
with weight
and value
. There may be repeated edges.
Output Specification
On one line you are to print the minimum maximum edge weight of the connected subgraph.
Subtasks
Subtask 1 (10%)
Subtask 2 (30%)
Subtask 3 (60%)
No further constraints.
Sample Input
4 4 5
1 2 2 1
2 3 3 2
3 4 4 3
4 1 1 4
Sample Output
-1
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