結果
問題 | No.1332 Range Nearest Query |
ユーザー | 草苺奶昔 |
提出日時 | 2024-05-03 17:21:27 |
言語 | Go (1.22.1) |
結果 |
AC
|
実行時間 | 656 ms / 2,500 ms |
コード長 | 18,713 bytes |
コンパイル時間 | 12,692 ms |
コンパイル使用メモリ | 221,236 KB |
実行使用メモリ | 18,688 KB |
最終ジャッジ日時 | 2024-05-03 17:22:06 |
合計ジャッジ時間 | 35,715 ms |
ジャッジサーバーID (参考情報) |
judge3 / judge5 |
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テストケース
テストケース表示入力 | 結果 | 実行時間 実行使用メモリ |
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testcase_00 | AC | 1 ms
5,248 KB |
testcase_01 | AC | 1 ms
5,376 KB |
testcase_02 | AC | 1 ms
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testcase_03 | AC | 600 ms
17,152 KB |
testcase_04 | AC | 553 ms
17,152 KB |
testcase_05 | AC | 580 ms
17,152 KB |
testcase_06 | AC | 456 ms
17,536 KB |
testcase_07 | AC | 457 ms
17,664 KB |
testcase_08 | AC | 430 ms
17,536 KB |
testcase_09 | AC | 432 ms
17,536 KB |
testcase_10 | AC | 427 ms
17,408 KB |
testcase_11 | AC | 412 ms
17,536 KB |
testcase_12 | AC | 464 ms
17,536 KB |
testcase_13 | AC | 448 ms
17,536 KB |
testcase_14 | AC | 409 ms
17,536 KB |
testcase_15 | AC | 457 ms
17,408 KB |
testcase_16 | AC | 600 ms
17,280 KB |
testcase_17 | AC | 597 ms
17,280 KB |
testcase_18 | AC | 605 ms
17,280 KB |
testcase_19 | AC | 587 ms
18,688 KB |
testcase_20 | AC | 617 ms
17,408 KB |
testcase_21 | AC | 603 ms
17,408 KB |
testcase_22 | AC | 611 ms
17,408 KB |
testcase_23 | AC | 591 ms
17,408 KB |
testcase_24 | AC | 623 ms
17,536 KB |
testcase_25 | AC | 620 ms
17,408 KB |
testcase_26 | AC | 408 ms
17,152 KB |
testcase_27 | AC | 348 ms
17,920 KB |
testcase_28 | AC | 103 ms
5,376 KB |
testcase_29 | AC | 104 ms
5,376 KB |
testcase_30 | AC | 106 ms
5,376 KB |
testcase_31 | AC | 93 ms
5,376 KB |
testcase_32 | AC | 109 ms
5,376 KB |
testcase_33 | AC | 107 ms
5,376 KB |
testcase_34 | AC | 106 ms
5,376 KB |
testcase_35 | AC | 113 ms
5,376 KB |
testcase_36 | AC | 112 ms
5,376 KB |
testcase_37 | AC | 117 ms
5,376 KB |
testcase_38 | AC | 471 ms
12,800 KB |
testcase_39 | AC | 239 ms
5,504 KB |
testcase_40 | AC | 656 ms
16,896 KB |
testcase_41 | AC | 303 ms
7,296 KB |
testcase_42 | AC | 432 ms
13,056 KB |
testcase_43 | AC | 339 ms
8,960 KB |
testcase_44 | AC | 510 ms
15,616 KB |
testcase_45 | AC | 495 ms
11,856 KB |
testcase_46 | AC | 385 ms
11,904 KB |
testcase_47 | AC | 529 ms
11,520 KB |
ソースコード
// 维护区间贡献的 Wavelet Matrix // !注意查询区间贡献时, 异或无效 // // api: // !RangeCountAndSum(start, end, a, b, xor) - 区间 [start, end) 中值在 [a, b) 之间的数的个数和这些数的和. // !KthValueAndSum(start, end, k, xor) - 区间 [start, end) 中第 k 小的数和前 k 小的数的和. // // Kth(start, end, k, xor) - 区间 [start, end) 中第 k 小的数. // Median(start, end, upper, xor) - 区间 [start, end) 中的中位数. // Floor(start, end, x, xor) - 区间 [start, end) 中值小于等于 x 的最大值 // Ceil(start, end, x, xor) - 区间 [start, end) 中值大于等于 x 的最小值 // // SumAll(start, end) - 区间 [start, end) 中所有数的和. // SumRange(start, end, a, b, xor) - 区间 [start, end) 中值在 [a, b) 之间的数的和. // SumSlice(start, end, k1, k2, xor) - 区间 [start, end) 中第 k1 到第 k2 小的数的和. // // MaxRight(start, end, xor, check) - 返回使得 check(count,prefixSum) 为 true 的最大(count,prefixSum), 其中prefixSum为[0,val)内的数的和. package main import ( "bufio" "fmt" "math/bits" "os" "sort" ) func main() { // demo() // yosupo_range_kth_smallest() // 区间最短距离和() // abc281_e() // yuki919() yuki1332() // yuki2065() } func demo() { nums := []int{1, 2, 3, 4, 5, 6, 7, 8, 9, 10} wm := NewWaveletMatrixWithSum(nums, nums, -1, true) fmt.Println(wm.RangeCountAndSum(0, 3, 3, 7, 0)) fmt.Println(wm.KthValueAndSum(1, 5, 0, 0)) nums = []int{1, 2, 3, 4, 5} wm = NewWaveletMatrixWithSum(nums, nums, -1, false) fmt.Println(wm.KthValueAndSum(0, 5, 2, 0)) fmt.Println(wm.KthValueAndSum(0, 6, 5, 0)) fmt.Println(wm.SumAll(0, 4)) fmt.Println(wm.Floor(0, 5, 4, 0)) fmt.Println(wm.Ceil(0, 5, 4, 0)) fmt.Println(wm.Kth(0, 5, 1, 0)) } // https://judge.yosupo.jp/problem/range_kth_smallest func yosupo_range_kth_smallest() { in := bufio.NewReader(os.Stdin) out := bufio.NewWriter(os.Stdout) defer out.Flush() var n, q int fmt.Fscan(in, &n, &q) nums := make([]int, n) for i := 0; i < n; i++ { fmt.Fscan(in, &nums[i]) } wm := NewWaveletMatrixWithSum(nums, nil, -1, false) for i := 0; i < q; i++ { var l, r, k int32 fmt.Fscan(in, &l, &r, &k) fmt.Fprintln(out, wm.Kth(l, r, k, 0)) } } func abc281_e() { in := bufio.NewReader(os.Stdin) out := bufio.NewWriter(os.Stdout) defer out.Flush() var n, m, k int32 fmt.Fscan(in, &n, &m, &k) nums := make([]int, n) for i := range nums { fmt.Fscan(in, &nums[i]) } wm := NewWaveletMatrixWithSum(nums, nums, -1, false) for i := int32(0); i < n-m+1; i++ { _, res := wm.KthValueAndSum(i, i+m, k, 0) fmt.Fprintln(out, res) } } // 子数组所有数到中位数的距离和(区间中位数距离和) // https://yukicoder.me/problems/no/924 // n,q<=2e5 // -1e9 <= nums[i] <= 1e9 // 给定n个查询[l,r] // !求区间[l,r]中位数到区间[l,r]中每个数的距离之和 // !也就求函数 f(x)= ∑|nums[i]-x| (l<=i<=right) 的最小值 // !区间中位数 func 区间最短距离和() { in := bufio.NewReader(os.Stdin) out := bufio.NewWriter(os.Stdout) defer out.Flush() var n, q int fmt.Fscan(in, &n, &q) OFFSET := int(1e9 + 10) nums := make([]int, n) for i := range nums { fmt.Fscan(in, &nums[i]) nums[i] += OFFSET } wm := NewWaveletMatrixWithSum(nums, nums, -1, false) for i := 0; i < q; i++ { var start, end int32 fmt.Fscan(in, &start, &end) start-- n := end - start lowerCount := n / 2 ceilCount := n - lowerCount mid, lowerSum := wm.KthValueAndSum(start, end, lowerCount, 0) allSum := wm.SumAll(start, end) ceilSum := allSum - lowerSum res := 0 res += mid*int(lowerCount) - lowerSum res += ceilSum - mid*int(ceilCount) fmt.Fprintln(out, res) } } // No.919 You Are A Project Manager (区间中位数+前后缀分解) // https://yukicoder.me/problems/no/919 // 给定一个数组nums,需要分为若干组. // 初始时选择分组大小k,每次分组需要从最左边或最右边取k个数分为一组, // 每个组的的得分为k*组内中位数(这里的中位数向下). // 求最大化总得分. // // n<=1e4,-1e9<=nums[i]<1e9 func yuki919() { in := bufio.NewReader(os.Stdin) out := bufio.NewWriter(os.Stdout) defer out.Flush() var n int32 fmt.Fscan(in, &n) nums := make([]int, n) for i := range nums { fmt.Fscan(in, &nums[i]) } wm := NewWaveletMatrixWithSum(nums, nil, -1, true) median := func(start, end int32) int { return wm.Median(start, end, false, 0) } res := -INF for size := int32(1); size <= n; size++ { count := n / size leftScore, rightScore := make([]int, count), make([]int, count) for i := int32(0); i < count; i++ { leftScore[i] = median(i*size, i*size+size) rightScore[i] = median(n-i*size-size, n-i*size) } leftPresum, rightPresum := make([]int, count+1), make([]int, count+1) for i := int32(0); i < count; i++ { leftPresum[i+1] = leftPresum[i] + leftScore[i] rightPresum[i+1] = rightPresum[i] + rightScore[i] } for i := int32(0); i < count; i++ { leftPresum[i+1] = max(leftPresum[i+1], leftPresum[i]) rightPresum[i+1] = max(rightPresum[i+1], rightPresum[i]) } for i := int32(0); i <= count; i++ { res = max(res, int(size)*(leftPresum[i]+rightPresum[count-i])) } } fmt.Fprintln(out, res) } // No.1332 Range Nearest Query // https://yukicoder.me/problems/no/1332 // 区间最近值(无序数组区间前驱后继)查询 // !对每个查询[left,right,x],输出左闭右开区间内的数到给定数x的最小距离 // n<=3e5 q<=1e5 nums[i]<=1e9 func yuki1332() { in := bufio.NewReader(os.Stdin) out := bufio.NewWriter(os.Stdout) defer out.Flush() var n int fmt.Fscan(in, &n) nums := make([]int, n) for i := 0; i < n; i++ { fmt.Fscan(in, &nums[i]) } M := NewWaveletMatrixWithSum(nums, nil, -1, true) var q int fmt.Fscan(in, &q) for i := 0; i < q; i++ { var start, end int32 var x int fmt.Fscan(in, &start, &end, &x) start-- res := INF floor := M.Floor(start, end, x, 0) // 小于等于x的最大值 if floor != -INF { res = min(res, abs(floor-x)) } ceiling := M.Ceil(start, end, x, 0) // 大于等于x的最小值 if ceiling != INF { res = min(res, abs(ceiling-x)) } fmt.Fprintln(out, res) } } // No.2065 Sum of Min (区间chmin之和) // https://yukicoder.me/problems/no/2065 // 小于x数的和+(end-start-小于x数的个数)*x func yuki2065() { in := bufio.NewReader(os.Stdin) out := bufio.NewWriter(os.Stdout) defer out.Flush() var n, q int32 fmt.Fscan(in, &n, &q) nums := make([]int, n) for i := range nums { fmt.Fscan(in, &nums[i]) } M := NewWaveletMatrixWithSum(nums, nums, -1, true) for i := int32(0); i < q; i++ { var start, end int32 var x int fmt.Fscan(in, &start, &end, &x) start-- lessCount, lessSum := M.RangeCountAndSum(start, end, 0, x, 0) // 小于x的数的个数 res := lessSum + int((end-start-lessCount))*x fmt.Fprintln(out, res) } } const INF WmValue = 1e18 type WmValue = int type WmSum = int func (*WaveletMatrixWithSum) e() WmSum { return 0 } func (*WaveletMatrixWithSum) op(a, b WmSum) WmSum { return a + b } func (*WaveletMatrixWithSum) inv(a WmSum) WmSum { return -a } type WaveletMatrixWithSum struct { n, log int32 setLog bool compress bool useSum bool mid []int32 bv []*BitVector key []WmValue presum [][]WmSum } // nums: 数组元素. // sumData: 和数据,nil表示不需要和数据. // log: 如果需要支持异或查询则需要传入log,-1表示默认. // compress: 是否对nums进行离散化(值域较大(1e9)时可以离散化加速). func NewWaveletMatrixWithSum(nums []WmValue, sumData []WmSum, log int32, compress bool) *WaveletMatrixWithSum { wm := &WaveletMatrixWithSum{} wm.build(nums, sumData, log, compress) return wm } func (wm *WaveletMatrixWithSum) build(nums []WmValue, sumData []WmSum, log int32, compress bool) { numsCopy := append(nums[:0:0], nums...) sumDataCopy := append(sumData[:0:0], sumData...) wm.n = int32(len(numsCopy)) wm.log = log wm.setLog = log != -1 wm.compress = compress wm.useSum = len(sumData) > 0 if wm.n == 0 { wm.log = 0 wm.presum = [][]WmSum{{wm.e()}} return } if compress { if wm.setLog { panic("compress and log should not be set at the same time") } wm.key = make([]WmValue, 0, wm.n) order := wm._argSort(numsCopy) for _, i := range order { if len(wm.key) == 0 || wm.key[len(wm.key)-1] != numsCopy[i] { wm.key = append(wm.key, numsCopy[i]) } numsCopy[i] = WmValue(len(wm.key) - 1) } wm.key = wm.key[:len(wm.key):len(wm.key)] } if wm.log == -1 { tmp := wm._maxs(numsCopy) if tmp < 1 { tmp = 1 } wm.log = int32(bits.Len(uint(tmp))) } wm.mid = make([]int32, wm.log) wm.bv = make([]*BitVector, wm.log) for i := range wm.bv { wm.bv[i] = NewBitVector(wm.n) } if wm.useSum { wm.presum = make([][]WmSum, 1+wm.log) for i := range wm.presum { sums := make([]WmSum, wm.n+1) for j := range sums { sums[j] = wm.e() } wm.presum[i] = sums } } if len(sumDataCopy) == 0 { sumDataCopy = make([]WmSum, len(numsCopy)) } A, S := numsCopy, sumDataCopy A0, A1 := make([]WmValue, wm.n), make([]WmValue, wm.n) S0, S1 := make([]WmSum, wm.n), make([]WmSum, wm.n) for d := wm.log - 1; d >= -1; d-- { p0, p1 := int32(0), int32(0) if wm.useSum { tmp := wm.presum[d+1] for i := int32(0); i < wm.n; i++ { tmp[i+1] = wm.op(tmp[i], S[i]) } } if d == -1 { break } for i := int32(0); i < wm.n; i++ { f := (A[i] >> d & 1) == 1 if !f { if wm.useSum { S0[p0] = S[i] } A0[p0] = A[i] p0++ } else { if wm.useSum { S1[p1] = S[i] } wm.bv[d].Set(i) A1[p1] = A[i] p1++ } } wm.mid[d] = p0 wm.bv[d].Build() A, A0 = A0, A S, S0 = S0, S for i := int32(0); i < p1; i++ { A[p0+i] = A1[i] S[p0+i] = S1[i] } } } // 返回区间 [start, end) 中 值在 [a, b) 中的元素个数以及这些元素的和. func (wm *WaveletMatrixWithSum) RangeCountAndSum(start, end int32, a, b WmValue, xorValue WmValue) (int32, WmSum) { if xorValue != 0 { if !wm.setLog { panic("log should be set when xor is used") } } if start < 0 { start = 0 } if end > wm.n { end = wm.n } if start >= end || a >= b { return 0, wm.e() } if wm.compress { a = wm._lowerBound(wm.key, a) b = wm._lowerBound(wm.key, b) } count, sum := int32(0), wm.e() var dfs func(d, l, r int32, lx, rx WmValue) dfs = func(d, l, r int32, lx, rx WmValue) { if rx <= a || b <= lx { return } if a <= lx && rx <= b { count += r - l if wm.useSum { sum = wm.op(sum, wm._get(d, l, r)) } return } d-- mx := (lx + rx) >> 1 l0, r0 := wm.bv[d].Rank(l, false), wm.bv[d].Rank(r, false) l1, r1 := l+wm.mid[d]-l0, r+wm.mid[d]-r0 if xorValue>>d&1 == 1 { l0, l1 = l1, l0 r0, r1 = r1, r0 } dfs(d, l0, r0, lx, mx) dfs(d, l1, r1, mx, rx) } dfs(wm.log, start, end, 0, 1<<wm.log) return count, sum } // 返回区间 [start, end) 中的 (第k小的元素, 前k个元素(不包括第k小的元素) 的 op 的结果). // 如果k >= end-start, 返回 (-1, 区间 op 的结果). func (wm *WaveletMatrixWithSum) KthValueAndSum(start, end, k int32, xorVal WmValue) (WmValue, WmSum) { if start < 0 { start = 0 } if end > wm.n { end = wm.n } if start >= end { return -1, wm.e() } if k >= end-start { return -1, wm.SumAll(start, end) } if xorVal != 0 { if !wm.setLog { panic("log should be set when xor is used") } } sum, val := wm.e(), WmValue(0) for d := wm.log - 1; d >= 0; d-- { l0, r0 := wm.bv[d].Rank(start, false), wm.bv[d].Rank(end, false) l1, r1 := start+wm.mid[d]-l0, end+wm.mid[d]-r0 if (xorVal>>d)&1 == 1 { l0, l1 = l1, l0 r0, r1 = r1, r0 } if k < r0-l0 { start, end = l0, r0 } else { k -= r0 - l0 val |= 1 << d start, end = l1, r1 if wm.useSum { sum = wm.op(sum, wm._get(d, l0, r0)) } } } if wm.useSum { sum = wm.op(sum, wm._get(0, start, start+k)) } if wm.compress { val = wm.key[val] } return val, sum } // [start, end)区间内第k(k>=0)小的元素. func (wm *WaveletMatrixWithSum) Kth(start, end, k int32, xorVal WmValue) WmValue { if k < 0 { k = 0 } if n := end - start - 1; k > n { k = n } v, _ := wm.KthValueAndSum(start, end, k, xorVal) return v } // upper: 向上取中位数还是向下取中位数. func (wm *WaveletMatrixWithSum) Median(start, end int32, upper bool, xorVal WmValue) WmValue { n := end - start var k int32 if upper { k = n >> 1 } else { k = (n - 1) >> 1 } return wm.Kth(start, end, k, xorVal) } // [start, end) 中小于等于 x 的数中最大的数. // // 如果不存在则返回-INF. func (wm *WaveletMatrixWithSum) Floor(start, end int32, x WmValue, xor WmValue) WmValue { if xor != 0 { if !wm.setLog { panic("log should be set when xor is used") } } if start < 0 { start = 0 } if end > wm.n { end = wm.n } if start >= end { return -INF } res := -INF x++ if wm.compress { x = wm._lowerBound(wm.key, x) } var dfs func(d, l, r int32, lx, rx WmValue) dfs = func(d, l, r int32, lx, rx WmValue) { if rx-1 <= res || l == r || x <= lx { return } if d == 0 { res = max(res, lx) return } d-- mx := (lx + rx) >> 1 l0, r0 := wm.bv[d].Rank(l, false), wm.bv[d].Rank(r, false) l1, r1 := l+wm.mid[d]-l0, r+wm.mid[d]-r0 if xor>>d&1 == 1 { l0, l1 = l1, l0 r0, r1 = r1, r0 } dfs(d, l1, r1, mx, rx) dfs(d, l0, r0, lx, mx) } dfs(wm.log, start, end, 0, 1<<wm.log) if wm.compress && res != -INF { res = wm.key[res] } return res } // [start, end) 中大于等于 x 的数中最小的数 // // 如果不存在则返回INF func (wm *WaveletMatrixWithSum) Ceil(start, end int32, x WmValue, xor WmValue) int { if xor != 0 { if !wm.setLog { panic("log should be set when xor is used") } } if start < 0 { start = 0 } if end > wm.n { end = wm.n } if start >= end { return INF } if wm.compress { x = wm._lowerBound(wm.key, x) } res := INF var dfs func(d, l, r int32, lx, rx WmValue) dfs = func(d, l, r int32, lx, rx WmValue) { if res <= lx || l == r || rx <= x { return } if d == 0 { res = min(res, lx) return } d-- mx := (lx + rx) >> 1 l0, r0 := wm.bv[d].Rank(l, false), wm.bv[d].Rank(r, false) l1, r1 := l+wm.mid[d]-l0, r+wm.mid[d]-r0 if xor>>d&1 == 1 { l0, l1 = l1, l0 r0, r1 = r1, r0 } dfs(d, l0, r0, lx, mx) dfs(d, l1, r1, mx, rx) } dfs(wm.log, start, end, 0, 1<<wm.log) if wm.compress && res < INF { res = wm.key[res] } return res } // 返回区间 [start, end) 中 范围在 [a, b) 中的元素的和. func (wm *WaveletMatrixWithSum) SumRange(start, end int32, a, b WmValue, xorVal WmValue) WmSum { if !wm.useSum { panic("sum data must be provided") } if start < 0 { start = 0 } if end > wm.n { end = wm.n } if start >= end || a >= b { return wm.e() } _, sum := wm.RangeCountAndSum(start, end, a, b, xorVal) return sum } // 返回区间 [start, end) 中 排名在 [k1, k2) 中的元素的和. func (wm *WaveletMatrixWithSum) SumSlice(start, end, k1, k2 int32, xorVal WmValue) WmSum { if !wm.useSum { panic("sum data must be provided") } if k1 < 0 { k1 = 0 } if k2 > end-start { k2 = end - start } if start < 0 { start = 0 } if end > wm.n { end = wm.n } if start >= end || k1 >= k2 { return wm.e() } _, sum1 := wm.KthValueAndSum(start, end, k1, xorVal) _, sum2 := wm.KthValueAndSum(start, end, k2, xorVal) return wm.op(sum2, wm.inv(sum1)) } func (wm *WaveletMatrixWithSum) SumAll(start, end int32) WmSum { if start < 0 { start = 0 } if end > wm.n { end = wm.n } if start >= end { return wm.e() } return wm._get(wm.log, start, end) } // 使得predicate(count, sum)为true的最大的(count, sum). func (wm *WaveletMatrixWithSum) MaxRight(predicate func(int32, WmSum) bool, start, end int32, xorVal WmValue) (int32, WmSum) { if xorVal != 0 { if !wm.setLog { panic("log should be set when xor is used") } } if start >= end { return 0, wm.e() } if s := wm._get(wm.log, start, end); predicate(end-start, s) { return end - start, s } count, sum := int32(0), wm.e() for d := wm.log - 1; d >= 0; d-- { l0, r0 := wm.bv[d].Rank(start, false), wm.bv[d].Rank(end, false) l1, r1 := start+wm.mid[d]-l0, end+wm.mid[d]-r0 if xorVal>>d&1 == 1 { l0, l1 = l1, l0 r0, r1 = r1, r0 } if s := wm.op(sum, wm._get(d, l0, r0)); predicate(count+r0-l0, s) { count += r0 - l0 sum = s start, end = l1, r1 } else { start, end = l0, r0 } } k := wm._binarySearch(func(k int32) bool { return predicate(count+k, wm.op(sum, wm._get(0, start, start+k))) }, 0, end-start) count += k sum = wm.op(sum, wm._get(0, start, start+k)) return count, sum } func (wm *WaveletMatrixWithSum) _get(d, l, r int32) WmSum { if wm.useSum { return wm.op(wm.presum[d][r], wm.inv(wm.presum[d][l])) } return wm.e() } func (wm *WaveletMatrixWithSum) _argSort(nums []WmValue) []int32 { order := make([]int32, len(nums)) for i := range order { order[i] = int32(i) } sort.Slice(order, func(i, j int) bool { return nums[order[i]] < nums[order[j]] }) return order } func (wm *WaveletMatrixWithSum) _maxs(nums []WmValue) WmValue { res := nums[0] for _, v := range nums { if v > res { res = v } } return res } func (wm *WaveletMatrixWithSum) _lowerBound(nums []WmValue, target WmValue) WmValue { left, right := int32(0), int32(len(nums)-1) for left <= right { mid := (left + right) >> 1 if nums[mid] < target { left = mid + 1 } else { right = mid - 1 } } return WmValue(left) } func (wm *WaveletMatrixWithSum) _binarySearch(f func(int32) bool, ok, ng int32) int32 { for abs32(ok-ng) > 1 { x := (ok + ng) >> 1 if f(x) { ok = x } else { ng = x } } return ok } type BitVector struct { bits []uint64 preSum []int32 } func NewBitVector(n int32) *BitVector { return &BitVector{bits: make([]uint64, n>>6+1), preSum: make([]int32, n>>6+1)} } func (bv *BitVector) Set(i int32) { bv.bits[i>>6] |= 1 << (i & 63) } func (bv *BitVector) Build() { for i := 0; i < len(bv.bits)-1; i++ { bv.preSum[i+1] = bv.preSum[i] + int32(bits.OnesCount64(bv.bits[i])) } } func (bv *BitVector) Rank(k int32, f bool) int32 { m, s := bv.bits[k>>6], bv.preSum[k>>6] res := s + int32(bits.OnesCount64(m&((1<<(k&63))-1))) if f { return res } return k - res } func abs(x int) int { if x < 0 { return -x } return x } func abs32(x int32) int32 { if x < 0 { return -x } return x } func min32(a, b int32) int32 { if a < b { return a } return b } func min(a, b int) int { if a < b { return a } return b } func max(a, b int) int { if a > b { return a } return b }