[1800][1A] CF1283D BFS

Author: EndlessCheng

main/1200-1299/1283D.go

@@ -0,0 +1,56 @@
+package main
+
+import (
+	"bufio"
+	. "fmt"
+	"io"
+)
+
+// github.com/EndlessCheng/codeforces-go
+func CF1283D(_r io.Reader, _w io.Writer) {
+	in := bufio.NewReader(_r)
+	out := bufio.NewWriter(_w)
+	defer out.Flush()
+
+	var n, m int
+	Fscan(in, &n, &m)
+	a := make([]int, n)
+	vis := make(map[int]bool, n+m*2)
+	for i := range a {
+		Fscan(in, &a[i])
+		vis[a[i]] = true
+	}
+	q := []int{}
+	add := func(v int) {
+		for i := v - 1; i < v+2; i += 2 {
+			if !vis[i] {
+				vis[i] = true
+				q = append(q, i)
+			}
+		}
+	}
+	for _, v := range a {
+		add(v)
+	}
+
+	ans := int64(0)
+	y := make([]int, 0, m)
+	for d := int64(1); ; d++ {
+		tmp := q
+		q = nil
+		for _, v := range tmp {
+			ans += d
+			y = append(y, v)
+			if len(y) == m {
+				Fprintln(out, ans)
+				for _, v := range y {
+					Fprint(out, v, " ")
+				}
+				return
+			}
+			add(v)
+		}
+	}
+}
+
+//func main() { CF1283D(os.Stdin, os.Stdout) }

main/1200-1299/1283D_test.go

@@ -0,0 +1,26 @@
+package main
+
+import (
+	"github.com/EndlessCheng/codeforces-go/main/testutil"
+	"testing"
+)
+
+// https://codeforces.com/problemset/problem/1283/D
+// https://codeforces.com/problemset/status/1283/problem/D
+func TestCF1283D(t *testing.T) {
+	// just copy from website
+	rawText := `
+inputCopy
+2 6
+1 5
+outputCopy
+8
+-1 2 6 4 0 3 
+inputCopy
+3 5
+0 3 1
+outputCopy
+7
+5 -2 4 -1 2 `
+	testutil.AssertEqualCase(t, rawText, 0, CF1283D)
+}