CF1593E

Author: EndlessCheng

main/1500-1599/1593E.go

@@ -0,0 +1,54 @@
+package main
+
+import (
+	"bufio"
+	. "fmt"
+	"io"
+)
+
+// github.com/EndlessCheng/codeforces-go
+func CF1593E(_r io.Reader, _w io.Writer) {
+	in := bufio.NewReader(_r)
+	out := bufio.NewWriter(_w)
+	defer out.Flush()
+
+	var T, n, k, v, w int
+	for Fscan(in, &T); T > 0; T-- {
+		Fscan(in, &n, &k)
+		g := make([][]int, n)
+		d := make([]int, n)
+		for i := 1; i < n; i++ {
+			Fscan(in, &v, &w)
+			v--
+			w--
+			g[v] = append(g[v], w)
+			g[w] = append(g[w], v)
+			d[v]++
+			d[w]++
+		}
+		if n < 3 {
+			Fprintln(out, 0)
+			continue
+		}
+		q := make([]int, 0, n)
+		for i, d := range d {
+			if d == 1 {
+				q = append(q, i)
+			}
+		}
+		for ; k > 0 && len(q) > 0; k-- {
+			sz := len(q)
+			for _, v := range q {
+				for _, w := range g[v] {
+					if d[w]--; d[w] == 1 {
+						q = append(q, w)
+					}
+				}
+			}
+			q = q[sz:]
+		}
+		Fprintln(out, cap(q))
+	}
+}
+
+//func main() { CF1593E(os.Stdin, os.Stdout) }

main/1500-1599/1593E_test.go

@@ -0,0 +1,66 @@
+package main
+
+import (
+	"github.com/EndlessCheng/codeforces-go/main/testutil"
+	"testing"
+)
+
+// https://codeforces.com/problemset/problem/1593/E
+// https://codeforces.com/problemset/status/1593/problem/E
+func TestCF1593E(t *testing.T) {
+	// just copy from website
+	rawText := `
+inputCopy
+6
+
+14 1
+1 2
+2 3
+2 4
+4 5
+4 6
+2 7
+7 8
+8 9
+8 10
+3 11
+3 12
+1 13
+13 14
+
+2 200000
+1 2
+
+3 2
+1 2
+2 3
+
+5 1
+5 1
+3 2
+2 1
+5 4
+
+6 2
+5 1
+2 5
+5 6
+4 2
+3 4
+
+7 1
+4 3
+5 1
+1 3
+6 1
+1 7
+2 1
+outputCopy
+7
+0
+0
+3
+1
+2`
+	testutil.AssertEqualCase(t, rawText, 0, CF1593E)
+}