const INF = 10^16 struct UnionFind par::Vector{Int} size::Vector{Int} UnionFind(N) = new(collect(1:N), collect(1:N)) end function root!(uf::UnionFind, x::Int) if uf.par[x] == x return x else return uf.par[x] = root!(uf, uf.par[x]) end end function issame!(uf::UnionFind, x::Int, y::Int) return root!(uf, x) == root!(uf, y) end function unite!(uf::UnionFind, x::Int, y::Int) x = root!(uf, x) y = root!(uf, y) (x == y) && (return true) if (uf.size[x] < uf.size[y]) uf.par[x] = y uf.size[y] += uf.size[x] else uf.par[y] = x uf.size[x] += uf.size[y] end return true end struct Edge from::Int to::Int weight::Int profit::Int end function reverse(edge::Edge) return Edge(edge.to, edge.from, edge.weight, edge.profit) end struct Graph edges::Vector{Vector{Edge}} function Graph(N) edges = [Vector{Edge}() for _ in 1:N] new(edges) end end function all_edges(graph::Graph)::Vector{Edge} return collect(Iterators.flatten(graph.edges)) end function add!(graph::Graph, edge::Edge; has_dir=false) push!(graph.edges[edge.from], edge) if !has_dir rev_edge = reverse(edge) push!(graph.edges[edge.to], rev_edge) end end function as_rooted_tree(graph::Graph, root::Int)::Graph N = length(graph.edges) tree = Graph(N) stack = [(root, -1)] while !isempty(stack) v, p = pop!(stack) for u in graph.edges[v] if u.to != p add!(tree, u, has_dir=true) push!(stack, (u.to, v)) end end end return tree end function kruskal(sorted_edges::Vector{Edge}, N)::Tuple{Graph,Int,Int} uf = UnionFind(N) graph = Graph(N) cost = 0 profit = -1 for edge in sorted_edges if !issame!(uf, edge.from, edge.to) unite!(uf, edge.from, edge.to) add!(graph, edge) cost += edge.weight profit = max(profit, edge.profit) end end return graph, cost, profit end struct LCA parent::Vector{Vector{Int}} dist::Vector{Vector{Int}} depth::Vector{Int} K::Int V::Int function LCA(graph::Graph; root=1) V = length(graph.edges) K = ceil(Int, log2(V)) tree = as_rooted_tree(graph, root) parent = [fill(-1, V) for _ in 1:K] dist = [fill(-1, V) for _ in 1:K] depth = fill(-1, V) stack = [(root, -1, 0)] while !isempty(stack) v, p, d = pop!(stack) depth[v] = d parent[1][v] = p for u in tree.edges[v] if u.to != p dist[1][u.to] = u.weight push!(stack, (u.to, v, d + 1)) end end end for k in 1:K-1 for v in 1:V if parent[k][v] == -1 continue else parent[k+1][v] = parent[k][parent[k][v]] dist[k+1][v] = max(dist[k][v], dist[k][parent[k][v]]) end end end return new(parent, dist, depth, K, V) end end function max_cost(lca::LCA, u::Int, v::Int)::Int cost = -INF if lca.depth[u] < lca.depth[v] u, v = v, u end diff = lca.depth[u] - lca.depth[v] for k in 0:lca.K-1 if (diff >> k) & 1 == 1 cost = max(cost, lca.dist[k+1][u]) u = lca.parent[k+1][u] end end if u == v return cost end for k in lca.K:-1:1 if lca.parent[k][u] != lca.parent[k][v] cost = max(cost, lca.dist[k][u]) cost = max(cost, lca.dist[k][v]) u = lca.parent[k][u] v = lca.parent[k][v] end end cost = max(cost, lca.dist[1][u]) cost = max(cost, lca.dist[1][v]) return cost end function main() N, K, C = parse.(Int, split(readline())) graph = Graph(N) for i in 1:K u, v, w, p = parse.(Int, split(readline())) edge = Edge(u, v, w, p) add!(graph, edge) end sorted_edges = all_edges(graph) sort!(sorted_edges, by=(x -> x.weight), rev=false) mst, C_m, P_m = kruskal(sorted_edges, N) mst_edges_set = Set{Edge}(all_edges(mst)) mst_tree = as_rooted_tree(mst, 1) lca = LCA(mst_tree) sort!(sorted_edges, by=(x -> x.profit), rev=true) i = 0 for edge in sorted_edges i += 1 P = edge.profit if (edge in mst_edges_set) C_add = 0 C_rem = 0 else u, v, C_add = edge.from, edge.to, edge.weight C_rem = max_cost(lca, u, v) end if C_m + C_add - C_rem <= C println(P) return end end println(-1) end main()