June 2018 Update

Task/Topological-sort/Julia/topological-sort.julia

@@ -0,0 +1,37 @@
+function toposort(data::Dict{T,Set{T}}) where T
+    data = copy(data)
+    for (k, v) in data
+        delete!(v, k)
+    end
+    extraitems = setdiff(reduce(∪, values(data)), keys(data))
+    for item in extraitems
+        data[item] = Set{T}()
+    end
+    rst = Vector{T}()
+    while true
+        ordered = Set(item for (item, dep) in data if isempty(dep))
+        if isempty(ordered) break end
+        append!(rst, ordered)
+        data = Dict{T,Set{T}}(item => setdiff(dep, ordered) for (item, dep) in data if item ∉ ordered)
+    end
+    @assert isempty(data) "a cyclic dependency exists amongst $(keys(data))"
+    return rst
+end
+
+data = Dict{String,Set{String}}(
+    "des_system_lib" => Set(split("std synopsys std_cell_lib des_system_lib dw02 dw01 ramlib ieee")),
+    "dw01" =>           Set(split("ieee dw01 dware gtech")),
+    "dw02" =>           Set(split("ieee dw02 dware")),
+    "dw03" =>           Set(split("std synopsys dware dw03 dw02 dw01 ieee gtech")),
+    "dw04" =>           Set(split("dw04 ieee dw01 dware gtech")),
+    "dw05" =>           Set(split("dw05 ieee dware")),
+    "dw06" =>           Set(split("dw06 ieee dware")),
+    "dw07" =>           Set(split("ieee dware")),
+    "dware" =>          Set(split("ieee dware")),
+    "gtech" =>          Set(split("ieee gtech")),
+    "ramlib" =>         Set(split("std ieee")),
+    "std_cell_lib" =>   Set(split("ieee std_cell_lib")),
+    "synopsys" =>       Set(),
+    )
+
+println("# Topologically sorted:\n - ", join(toposort(data), "\n - "))