aaa

src/codeforces/set0/set9/set980/set985/c/problem.md

@@ -0,0 +1,9 @@
+You have m = n·k wooden staves. The i-th stave has length ai. You have to assemble n barrels consisting of k staves each, you can use any k staves to construct a barrel. Each stave must belong to exactly one barrel.
+
+Let volume vj of barrel j be equal to the length of the minimal stave in it.
+
+
+You want to assemble exactly n barrels with the maximal total sum of volumes. But you have to make them equal enough, so a difference between volumes of any pair of the resulting barrels must not exceed l, i.e. |vx - vy| ≤ l for any 1 ≤ x ≤ n and 1 ≤ y ≤ n.
+
+Print maximal total sum of volumes of equal enough barrels or 0 if it's impossible to satisfy the condition above.
+

src/codeforces/set0/set9/set980/set985/c/solution.go

@@ -0,0 +1,109 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"sort"
+)
+
+func main() {
+	reader := bufio.NewReader(os.Stdin)
+	n, k, l := readThreeNums(reader)
+	a := readNNums(reader, n*k)
+	fmt.Println(solve(a, k, l))
+}
+
+func readInt(bytes []byte, from int, val *int) int {
+	i := from
+	sign := 1
+	if bytes[i] == '-' {
+		sign = -1
+		i++
+	}
+	tmp := 0
+	for i < len(bytes) && bytes[i] >= '0' && bytes[i] <= '9' {
+		tmp = tmp*10 + int(bytes[i]-'0')
+		i++
+	}
+	*val = tmp * sign
+	return i
+}
+
+func readNum(reader *bufio.Reader) (a int) {
+	bs, _ := reader.ReadBytes('\n')
+	readInt(bs, 0, &a)
+	return
+}
+
+func readTwoNums(reader *bufio.Reader) (a int, b int) {
+	res := readNNums(reader, 2)
+	a, b = res[0], res[1]
+	return
+}
+
+func readThreeNums(reader *bufio.Reader) (a int, b int, c int) {
+	res := readNNums(reader, 3)
+	a, b, c = res[0], res[1], res[2]
+	return
+}
+
+func readNNums(reader *bufio.Reader, n int) []int {
+	res := make([]int, n)
+	x := 0
+	bs, _ := reader.ReadBytes('\n')
+	for i := 0; i < n; i++ {
+		for x < len(bs) && (bs[x] < '0' || bs[x] > '9') && bs[x] != '-' {
+			x++
+		}
+		x = readInt(bs, x, &res[i])
+	}
+	return res
+}
+
+func solve(a []int, k int, l int) int {
+	sort.Ints(a)
+
+	n := len(a)
+
+	vis := make([]bool, n)
+
+	it := sort.Search(n, func(i int) bool {
+		return a[i]-a[0] > l
+	})
+	if it < n/k {
+		return 0
+	}
+	it--
+	// a[it] - a[0] <= l
+	var res int
+	r := n - 1
+	// stage 1
+	for i := it; i >= 0; i-- {
+		if r-it < k-1 {
+			break
+		}
+		var cnt int
+		for cnt < k-1 {
+			vis[r] = true
+			cnt++
+			r--
+		}
+		res += a[i]
+		vis[i] = true
+	}
+
+	for i := n - 1; i >= 0; {
+		var cnt int
+		for i >= 0 && cnt < k {
+			if !vis[i] {
+				cnt++
+			}
+			i--
+		}
+		if cnt == k {
+			res += a[i+1]
+		}
+	}
+	return res
+}

src/codeforces/set0/set9/set980/set985/c/solution_test.go

@@ -0,0 +1,39 @@
+package main
+
+import "testing"
+
+func runSample(t *testing.T, a []int, k int, l int, expect int) {
+	res := solve(a, k, l)
+
+	if res != expect {
+		t.Fatalf("Sample expect %d, but got %d", expect, res)
+	}
+}
+
+func TestSample1(t *testing.T) {
+	k, l := 2, 1
+	a := []int{2, 2, 1, 2, 3, 2, 2, 3}
+	expect := 7
+	runSample(t, a, k, l, expect)
+}
+
+func TestSample2(t *testing.T) {
+	k, l := 1, 0
+	a := []int{10, 10}
+	expect := 20
+	runSample(t, a, k, l, expect)
+}
+
+func TestSample3(t *testing.T) {
+	k, l := 2, 1
+	a := []int{5, 2}
+	expect := 2
+	runSample(t, a, k, l, expect)
+}
+
+func TestSample4(t *testing.T) {
+	k, l := 2, 1
+	a := []int{1, 2, 3, 4, 5, 6}
+	expect := 0
+	runSample(t, a, k, l, expect)
+}

src/codeforces/set1/set17/set179/set1793/d/problem.md

@@ -0,0 +1,60 @@
+In winter, the inhabitants of the Moscow Zoo are very bored, in particular, it concerns gorillas. You decided to entertain them and brought a permutation 𝑝
+ of length 𝑛
+ to the zoo.
+
+A permutation of length 𝑛
+ is an array consisting of 𝑛
+ distinct integers from 1
+ to 𝑛
+ in any order. For example, [2,3,1,5,4]
+ is a permutation, but [1,2,2]
+ is not a permutation (2
+ occurs twice in the array) and [1,3,4]
+ is also not a permutation (𝑛=3
+, but 4
+ is present in the array).
+
+The gorillas had their own permutation 𝑞
+ of length 𝑛
+. They suggested that you count the number of pairs of integers 𝑙,𝑟
+ (1≤𝑙≤𝑟≤𝑛
+) such that MEX([𝑝𝑙,𝑝𝑙+1,…,𝑝𝑟])=MEX([𝑞𝑙,𝑞𝑙+1,…,𝑞𝑟])
+.
+
+The MEX
+ of the sequence is the minimum integer positive number missing from this sequence. For example, MEX([1,3])=2
+, MEX([5])=1
+, MEX([3,1,2,6])=4
+.
+
+You do not want to risk your health, so you will not dare to refuse the gorillas.
+
+
+### ideas
+1. 略一思考，还有点难～
+2. 假设p[i] = 0, q[j] = 0,
+3. 那么任何不包括(i, j)的区间[l...r]它们的mex = 0
+4. 那是不是就可以这样算呢？
+5. 不包括(i, j)的区间 = 总区间数 n * (n + 1) / 2 - 包含它们的区间数 = (i+1) * (n - j) ?
+6. 前面处理的是 mex = 0的情况， 
+7. 接下来处理mex = 1的情况（它们必须把0包括进去）
+8. 好像不大对，比如如果0在两头的时候
+9. 那些mex = 0 的区间 = 肯定不包含任何一个0的区间
+10. 正难则反。有办法计算出，区间[l...r]中 mex(q) != mex(p)的方式吗？
+11. 假设 mex(p[l..r]) = x, mex(q[l...r]) = y
+12. 它们不相同
+13. 考虑一个序列，如何找到mex
+14. 假设序列是 [2,3,1,5,4],
+15. mex[3:3] = 2, 其他的等于 1
+16. mex[1:3] = 4, 其他的等于 1
+17. mex[1:5] = 6, 其他的等于1
+18. [1 3 2], [2 1 3]
+19. p_mex[1:2] = 2, q_mex[1:2] = 3 但是其他都等于1 
+20. p_mex[1:3] = 4, q_mex[1:3] = 4
+21. [4, 1, 3, 2], [4, 3, 1, 2]
+22. [4, 1, 3] mex = 2
+23. [4, 3, 1] mex = 2
+24. 这个区间[1:3]它就是包含了1,但是不包含2，所以这样是这样的区间它们的mex = 2
+25. 所以如果某个区间包含了1....x-1, 但是不包含x,那么这样的区间是相等的
+26. mex = 0的区间假设已经get到了
+27. 那么计算 mex = x的区间，就可以用到上面的方式

src/codeforces/set1/set17/set179/set1793/d/solution.go

@@ -0,0 +1,128 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+)
+
+func main() {
+	reader := bufio.NewReader(os.Stdin)
+
+	n := readNum(reader)
+	p := readNNums(reader, n)
+	q := readNNums(reader, n)
+	res := solve(p, q)
+	fmt.Println(res)
+}
+
+func readString(reader *bufio.Reader) string {
+	s, _ := reader.ReadString('\n')
+	for i := 0; i < len(s); i++ {
+		if s[i] == '\n' || s[i] == '\r' {
+			return s[:i]
+		}
+	}
+	return s
+}
+
+func readInt(bytes []byte, from int, val *int) int {
+	i := from
+	sign := 1
+	if bytes[i] == '-' {
+		sign = -1
+		i++
+	}
+	tmp := 0
+	for i < len(bytes) && bytes[i] >= '0' && bytes[i] <= '9' {
+		tmp = tmp*10 + int(bytes[i]-'0')
+		i++
+	}
+	*val = tmp * sign
+	return i
+}
+
+func readNum(reader *bufio.Reader) (a int) {
+	bs, _ := reader.ReadBytes('\n')
+	readInt(bs, 0, &a)
+	return
+}
+
+func readTwoNums(reader *bufio.Reader) (a int, b int) {
+	res := readNNums(reader, 2)
+	a, b = res[0], res[1]
+	return
+}
+
+func readThreeNums(reader *bufio.Reader) (a int, b int, c int) {
+	res := readNNums(reader, 3)
+	a, b, c = res[0], res[1], res[2]
+	return
+}
+
+func readNNums(reader *bufio.Reader, n int) []int {
+	res := make([]int, n)
+	x := 0
+	bs, _ := reader.ReadBytes('\n')
+	for i := 0; i < n; i++ {
+		for x < len(bs) && (bs[x] < '0' || bs[x] > '9') && bs[x] != '-' {
+			x++
+		}
+		x = readInt(bs, x, &res[i])
+	}
+	return res
+}
+
+func solve(p []int, q []int) int {
+	n := len(p)
+	for i := 0; i < n; i++ {
+		p[i]--
+		q[i]--
+	}
+
+	ps := getPosition(p)
+	qs := getPosition(q)
+
+	first := min(ps[0], qs[0])
+	last := max(ps[0], qs[0])
+
+	get := func(m int) int {
+		if m <= 0 {
+			return 0
+		}
+		return m * (m + 1) / 2
+	}
+
+	// mex = 0 的区间
+	var res int
+	res += get(first)
+	res += get(last - first - 1)
+	res += get(n - last - 1)
+
+	for x := 1; x < n; x++ {
+		l := min(ps[x], qs[x])
+		r := max(ps[x], qs[x])
+		// mex = x的区间， 必须包含 [first...last], 但是不能包含(l, r)
+		if l < first && last < r {
+			res += (first - l) * (r - last)
+		} else if l > last {
+			res += (first + 1) * (l - last)
+		} else if r < first {
+			res += (first - r) * (n - last)
+		}
+
+		first = min(first, l)
+		last = max(last, r)
+	}
+
+	return res + 1
+}
+
+func getPosition(nums []int) []int {
+	n := len(nums)
+	pos := make([]int, n)
+	for i, num := range nums {
+		pos[num] = i
+	}
+	return pos
+}

src/codeforces/set1/set17/set179/set1793/d/solution_test.go

@@ -0,0 +1,32 @@
+package main
+
+import "testing"
+
+func runSample(t *testing.T, p []int, q []int, expect int) {
+	res := solve(p, q)
+
+	if res != expect {
+		t.Fatalf("Sample expect %d, but got %d", expect, res)
+	}
+}
+
+func TestSample1(t *testing.T) {
+	a := []int{1, 3, 2}
+	b := []int{2, 1, 3}
+	expect := 2
+	runSample(t, a, b, expect)
+}
+
+func TestSample2(t *testing.T) {
+	a := []int{7, 3, 6, 2, 1, 5, 4}
+	b := []int{6, 7, 2, 5, 3, 1, 4}
+	expect := 16
+	runSample(t, a, b, expect)
+}
+
+func TestSample3(t *testing.T) {
+	a := []int{1, 2, 3, 4, 5, 6}
+	b := []int{6, 5, 4, 3, 2, 1}
+	expect := 11
+	runSample(t, a, b, expect)
+}