Skip to content

feat: add solution to lc problem: No.3485 #4340

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 3 commits into from
Apr 9, 2025
Merged

feat: add solution to lc problem: No.3485 #4340

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
224bc16
Update code for cpp in README_EN.md
Parth-Dholariya Apr 9, 2025
ccdbf29
Add Java and C++ solutions for problem 3485.
yanglbme Apr 9, 2025
3a7f332
Format SegmentTree constructor initialization list
yanglbme Apr 9, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
239 changes: 237 additions & 2 deletions solution/3400-3499/3485.Longest Common Prefix of K Strings After Removal/README.md
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -114,13 +114,248 @@ tags:
#### Java

```java

class Solution {
static class TrieNode {
int count = 0;
int depth = 0;
int[] children = new int[26];

TrieNode() {
for (int i = 0; i < 26; ++i) children[i] = -1;
}
}

static class SegmentTree {
int n;
int[] tree;
int[] globalCount;

SegmentTree(int n, int[] globalCount) {
this.n = n;
this.globalCount = globalCount;
this.tree = new int[4 * (n + 1)];
for (int i = 0; i < tree.length; i++) tree[i] = -1;
build(1, 1, n);
}

void build(int idx, int l, int r) {
if (l == r) {
tree[idx] = globalCount[l] > 0 ? l : -1;
return;
}
int mid = (l + r) / 2;
build(idx * 2, l, mid);
build(idx * 2 + 1, mid + 1, r);
tree[idx] = Math.max(tree[idx * 2], tree[idx * 2 + 1]);
}

void update(int idx, int l, int r, int pos, int newVal) {
if (l == r) {
tree[idx] = newVal > 0 ? l : -1;
return;
}
int mid = (l + r) / 2;
if (pos <= mid) {
update(idx * 2, l, mid, pos, newVal);
} else {
update(idx * 2 + 1, mid + 1, r, pos, newVal);
}
tree[idx] = Math.max(tree[idx * 2], tree[idx * 2 + 1]);
}

int query() {
return tree[1];
}
}

public int[] longestCommonPrefix(String[] words, int k) {
int n = words.length;
int[] ans = new int[n];
if (n - 1 < k) return ans;

ArrayList<TrieNode> trie = new ArrayList<>();
trie.add(new TrieNode());

for (String word : words) {
int cur = 0;
for (char c : word.toCharArray()) {
int idx = c - 'a';
if (trie.get(cur).children[idx] == -1) {
trie.get(cur).children[idx] = trie.size();
TrieNode node = new TrieNode();
node.depth = trie.get(cur).depth + 1;
trie.add(node);
}
cur = trie.get(cur).children[idx];
trie.get(cur).count++;
}
}

int maxDepth = 0;
for (int i = 1; i < trie.size(); ++i) {
if (trie.get(i).count >= k) {
maxDepth = Math.max(maxDepth, trie.get(i).depth);
}
}

int[] globalCount = new int[maxDepth + 1];
for (int i = 1; i < trie.size(); ++i) {
TrieNode node = trie.get(i);
if (node.count >= k && node.depth <= maxDepth) {
globalCount[node.depth]++;
}
}

List<List<Integer>> fragileList = new ArrayList<>();
for (int i = 0; i < n; ++i) {
fragileList.add(new ArrayList<>());
}

for (int i = 0; i < n; ++i) {
int cur = 0;
for (char c : words[i].toCharArray()) {
int idx = c - 'a';
cur = trie.get(cur).children[idx];
if (trie.get(cur).count == k) {
fragileList.get(i).add(trie.get(cur).depth);
}
}
}

int segSize = maxDepth;
if (segSize >= 1) {
SegmentTree segTree = new SegmentTree(segSize, globalCount);
for (int i = 0; i < n; ++i) {
if (n - 1 < k) {
ans[i] = 0;
} else {
for (int d : fragileList.get(i)) {
segTree.update(1, 1, segSize, d, globalCount[d] - 1);
}
int res = segTree.query();
ans[i] = res == -1 ? 0 : res;
for (int d : fragileList.get(i)) {
segTree.update(1, 1, segSize, d, globalCount[d]);
}
}
}
}

return ans;
}
}
```

#### C++

```cpp

class Solution {
public:
struct TrieNode {
int count = 0;
int depth = 0;
int children[26] = {0};
};

class SegmentTree {
public:
int n;
vector<int> tree;
vector<int>& globalCount;
SegmentTree(int n, vector<int>& globalCount)
: n(n)
, globalCount(globalCount) {
tree.assign(4 * (n + 1), -1);
build(1, 1, n);
}
void build(int idx, int l, int r) {
if (l == r) {
tree[idx] = globalCount[l] > 0 ? l : -1;
return;
}
int mid = (l + r) / 2;
build(idx * 2, l, mid);
build(idx * 2 + 1, mid + 1, r);
tree[idx] = max(tree[idx * 2], tree[idx * 2 + 1]);
}
void update(int idx, int l, int r, int pos, int newVal) {
if (l == r) {
tree[idx] = newVal > 0 ? l : -1;
return;
}
int mid = (l + r) / 2;
if (pos <= mid)
update(idx * 2, l, mid, pos, newVal);
else
update(idx * 2 + 1, mid + 1, r, pos, newVal);
tree[idx] = max(tree[idx * 2], tree[idx * 2 + 1]);
}
int query() {
return tree[1];
}
};

vector<int> longestCommonPrefix(vector<string>& words, int k) {
int n = words.size();
vector<int> ans(n, 0);
if (n - 1 < k) return ans;
vector<TrieNode> trie(1);
for (const string& word : words) {
int cur = 0;
for (char c : word) {
int idx = c - 'a';
if (trie[cur].children[idx] == 0) {
trie[cur].children[idx] = trie.size();
trie.push_back({0, trie[cur].depth + 1});
}
cur = trie[cur].children[idx];
trie[cur].count++;
}
}
int maxDepth = 0;
for (int i = 1; i < trie.size(); ++i) {
if (trie[i].count >= k) {
maxDepth = max(maxDepth, trie[i].depth);
}
}
vector<int> globalCount(maxDepth + 1, 0);
for (int i = 1; i < trie.size(); ++i) {
if (trie[i].count >= k && trie[i].depth <= maxDepth) {
globalCount[trie[i].depth]++;
}
}
vector<vector<int>> fragileList(n);
for (int i = 0; i < n; ++i) {
int cur = 0;
for (char c : words[i]) {
int idx = c - 'a';
cur = trie[cur].children[idx];
if (trie[cur].count == k) {
fragileList[i].push_back(trie[cur].depth);
}
}
}
int segSize = maxDepth;
if (segSize >= 1) {
SegmentTree segTree(segSize, globalCount);
for (int i = 0; i < n; ++i) {
if (n - 1 < k) {
ans[i] = 0;
} else {
for (int d : fragileList[i]) {
segTree.update(1, 1, segSize, d, globalCount[d] - 1);
}
int res = segTree.query();
ans[i] = res == -1 ? 0 : res;
for (int d : fragileList[i]) {
segTree.update(1, 1, segSize, d, globalCount[d]);
}
}
}
}
return ans;
}
};
```

#### Go
Expand Down
Loading