/****************************************************************************
* Data files: http://algs4.cs.princeton.edu/15uf/tinyUF.txt
* http://algs4.cs.princeton.edu/15uf/mediumUF.txt
* http://algs4.cs.princeton.edu/15uf/largeUF.txt
*
* % ./uf < tinyUF.txt
* 4 3
* 3 8
* 6 5
* 9 4
* 2 1
* 5 0
* 7 2
* 6 1
* 2 components
*
****************************************************************************/
func main() {
var n int
stdin := stdin.NewStdin()
if !stdin.IsEmpty() {
n, _ = stdin.ReadInt()
} else {
panic("No input...")
}
// uf := uf.NewQuickFind(n) // initialize n components
// uf := uf.NewQuickUnion(n) // initialize n components
// uf := uf.NewWeightedQuickUnion(n) // initialize n components
uf := uf.NewWeightedQuickUnionWithPathCompression(n) // initialize n components
var p, q int
for !stdin.IsEmpty() {
p, _ = stdin.ReadInt()
if !stdin.IsEmpty() {
q, _ = stdin.ReadInt() // read pair to connect
}
if uf.Connected(p, q) { // ignore if connected
continue
}
uf.Union(p, q) // combine components
fmt.Printf("%d %d\n", p, q) // print connection
}
fmt.Printf("%d components\n", uf.Count())
}
// This program takes the name of a whitelist file (a sequence of integers) as argument and filters any
// entry that is on the whitelist from standard input, leaving only integers that are not on the whitelist
// on standard output. It uses the binary search algorithm, implemented in the method Rank(),
// to accomplish the task efficiently.
func main() {
if len(os.Args) <= 1 {
fmt.Printf("usage: %s tinyW.txt < tinyT.txt\n", filepath.Base(os.Args[0]))
return
}
whitelist, err := in.ReadAllIntsFromFile(os.Args[1])
if err != nil {
log.Fatal(err)
}
sort.Ints(whitelist)
stdin := stdin.NewStdin()
for !stdin.IsEmpty() {
// Read key, print if not in whitelist
key, err := stdin.ReadInt()
if err != nil {
log.Fatal(err)
}
if bsearch.Rank(key, whitelist) == -1 {
fmt.Println(key)
}
}
}