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| 1 | +/** |
| 2 | + * @param {string} s |
| 3 | + * @param {string} queryCharacters |
| 4 | + * @param {number[]} queryIndices |
| 5 | + * @return {number[]} |
| 6 | + */ |
| 7 | +const longestRepeating = function(s, queryCharacters, queryIndices) { |
| 8 | + let n = queryCharacters.length |
| 9 | + const ans = [] |
| 10 | + |
| 11 | + const segmentTree = new SegmentTree(s) |
| 12 | + for (let i = 0; i < n; i++) { |
| 13 | + segmentTree.update(1, 0, s.length - 1, queryIndices[i], queryCharacters[i]) |
| 14 | + ans.push(segmentTree.getMax()) |
| 15 | + } |
| 16 | + |
| 17 | + return ans |
| 18 | +}; |
| 19 | + |
| 20 | +class TreeNode { |
| 21 | + constructor(max, preStart, preEnd, sufStart, sufEnd) { |
| 22 | + this.max = max |
| 23 | + this.preStart = preStart |
| 24 | + this.preEnd = preEnd |
| 25 | + this.sufStart = sufStart |
| 26 | + this.sufEnd = sufEnd |
| 27 | + } |
| 28 | +} |
| 29 | + |
| 30 | +class SegmentTree { |
| 31 | + constructor(s) { |
| 32 | + this.n = s.length |
| 33 | + this.s = s.split('') |
| 34 | + this.tree = new Array(4 * s.length) |
| 35 | + this.build(s, 1, 0, s.length - 1) |
| 36 | + } |
| 37 | + |
| 38 | + build(s, treeIndex, left, right) { |
| 39 | + if (left === right) { |
| 40 | + this.tree[treeIndex] = new TreeNode(1, left, left, right, right) |
| 41 | + return |
| 42 | + } |
| 43 | + |
| 44 | + let mid = left + Math.floor((right - left) / 2) |
| 45 | + this.build(s, treeIndex * 2, left, mid) |
| 46 | + this.build(s, treeIndex * 2 + 1, mid + 1, right) |
| 47 | + |
| 48 | + this.tree[treeIndex] = this.merge( |
| 49 | + this.tree[treeIndex * 2], |
| 50 | + this.tree[treeIndex * 2 + 1], |
| 51 | + left, |
| 52 | + mid, |
| 53 | + right |
| 54 | + ) |
| 55 | + } |
| 56 | + |
| 57 | + update(treeIndex, left, right, index, val) { |
| 58 | + if (left === right) { |
| 59 | + this.tree[treeIndex] = new TreeNode(1, left, left, right, right) |
| 60 | + this.s[index] = val |
| 61 | + return |
| 62 | + } |
| 63 | + |
| 64 | + let mid = left + Math.floor((right - left) / 2) |
| 65 | + if (mid < index) { |
| 66 | + this.update(treeIndex * 2 + 1, mid + 1, right, index, val) |
| 67 | + } else { |
| 68 | + this.update(treeIndex * 2, left, mid, index, val) |
| 69 | + } |
| 70 | + |
| 71 | + this.tree[treeIndex] = this.merge( |
| 72 | + this.tree[treeIndex * 2], |
| 73 | + this.tree[treeIndex * 2 + 1], |
| 74 | + left, |
| 75 | + mid, |
| 76 | + right |
| 77 | + ) |
| 78 | + } |
| 79 | + |
| 80 | + merge(l, r, left, mid, right) { |
| 81 | + let max = Math.max(l.max, r.max) |
| 82 | + let preStart = l.preStart |
| 83 | + let preEnd = l.preEnd |
| 84 | + let sufStart = r.sufStart |
| 85 | + let sufEnd = r.sufEnd |
| 86 | + |
| 87 | + if (this.s[mid] === this.s[mid + 1]) { |
| 88 | + max = Math.max(max, r.preEnd - l.sufStart + 1) |
| 89 | + if (l.preEnd - l.preStart + 1 === mid - left + 1) { |
| 90 | + preEnd = r.preEnd |
| 91 | + } |
| 92 | + if (r.sufEnd - r.sufStart + 1 === right - mid) { |
| 93 | + sufStart = l.sufStart |
| 94 | + } |
| 95 | + } |
| 96 | + |
| 97 | + return new TreeNode(max, preStart, preEnd, sufStart, sufEnd) |
| 98 | + } |
| 99 | + |
| 100 | + getMax() { |
| 101 | + return this.tree[1].max |
| 102 | + } |
| 103 | +} |
| 104 | + |
| 105 | + |
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