Zengtudor/alg2025
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

update

Browse Source
This commit is contained in:
Zengtudor 2025-03-15 10:00:12 +08:00
parent fb65b9e085
commit b552887e66
3 changed files with 242 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

141
src/2/22/T294677.cpp Normal file
View File

@ -0,0 +1,141 @@
#include <bits/stdc++.h>
using namespace std;
struct SegmentTree {
int n;
vector<int> tree;
SegmentTree(int size) {
n = size;
tree.assign(4 * n + 4, 0);
}
void build(vector<int> &last, int node, int l, int r) {
if (l == r) {
tree[node] = last[l];
} else {
int mid = (l + r) / 2;
build(last, 2 * node, l, mid);
build(last, 2 * node + 1, mid + 1, r);
tree[node] = max(tree[2 * node], tree[2 * node + 1]);
}
}
void upd(int node, int l, int r, int pos, int val) {
if (l == r) {
tree[node] = val;
} else {
int mid = (l + r) / 2;
if (pos <= mid)
upd(2 * node, l, mid, pos, val);
else
upd(2 * node + 1, mid + 1, r, pos, val);
tree[node] = max(tree[2 * node], tree[2 * node + 1]);
}
}
int getmax(int node, int l, int r, int L, int R) {
if (r < L || l > R)
return -1;
if (L <= l && r <= R)
return tree[node];
int mid = (l + r) / 2;
return max(getmax(2 * node, l, mid, L, R),
getmax(2 * node + 1, mid + 1, r, L, R));
}
};
int main() {
ios::sync_with_stdio(false);
cin.tie(0);
int n, q;
cin >> n >> q;
vector<int> a(n + 1);
for (int i = 1; i <= n; i++)
cin >> a[i];
const int MAX_COLOR = 1000001;
vector<set<int> *> cp(MAX_COLOR, nullptr);
for (int i = 1; i <= n; i++) {
int c = a[i];
if (cp[c] == nullptr) {
cp[c] = new set<int>();
}
cp[c]->insert(i);
}
vector<int> last(n + 1, 0);
for (int c = 0; c < MAX_COLOR; c++) {
if (cp[c] == nullptr)
continue;
int prev = 0;
for (auto it = cp[c]->begin(); it != cp[c]->end();
++it) {
int pos = *it;
last[pos] = prev;
prev = pos;
}
}
SegmentTree st(n);
st.build(last, 1, 1, n);
while (q--) {
int type;
cin >> type;
if (type == 1) {
int id, x;
cin >> id >> x;
int c_old = a[id];
if (c_old == x) {
continue;
}
if (cp[c_old] != nullptr) {
auto it_old = cp[c_old]->find(id);
if (it_old != cp[c_old]->end()) {
int p_prev = 0;
if (it_old != cp[c_old]->begin()) {
auto it_prev = it_old;
--it_prev;
p_prev = *it_prev;
}
auto it_next = it_old;
++it_next;
if (it_next != cp[c_old]->end()) {
int p_next = *it_next;
last[p_next] = p_prev;
st.upd(1, 1, n, p_next, last[p_next]);
}
cp[c_old]->erase(it_old);
}
}
if (cp[x] == nullptr) {
cp[x] = new set<int>();
}
auto &s_new = *cp[x];
auto it_new = s_new.lower_bound(id);
int ppn = 0;
if (it_new != s_new.begin()) {
auto it_prev_new = it_new;
--it_prev_new;
ppn = *it_prev_new;
}
int pnn = 0;
if (it_new != s_new.end()) {
pnn = *it_new;
}
s_new.insert(id);
last[id] = ppn;
st.upd(1, 1, n, id, last[id]);
if (pnn != 0) {
last[pnn] = id;
st.upd(1, 1, n, pnn, last[pnn]);
}
a[id] = x;
} else if (type == 2) {
int l, r;
cin >> l >> r;
int max_last = st.getmax(1, 1, n, l, r);
if (max_last >= l) {
cout << "yes\n";
} else {
cout << "no\n";
}
}
}
for (int c = 0; c < MAX_COLOR; c++)
if (cp[c] != nullptr)
delete cp[c];
}

98
src/2/22/T461834.cpp Normal file
View File

@ -0,0 +1,98 @@
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int MAX = 300005;
const int MOD = 998244353;
ll c[MAX];
ll psc[MAX];
ll a_init[MAX];
struct SegNode {
int l, r;
ll sum_a_c;
ll lazy;
} tree_nodes[4 * MAX];
int n, m;
ll safe(ll x, ll y) { return (x - y + MOD) % MOD; }
void build(int node, int l, int r) {
tree_nodes[node].l = l;
tree_nodes[node].r = r;
tree_nodes[node].lazy = -1;
if (l == r) {
tree_nodes[node].sum_a_c = (a_init[l] % MOD) * c[l] % MOD;
return;
}
int mid = (l + r) / 2;
build(2 * node, l, mid);
build(2 * node + 1, mid + 1, r);
tree_nodes[node].sum_a_c =
(tree_nodes[2 * node].sum_a_c + tree_nodes[2 * node + 1].sum_a_c) % MOD;
}
void pushdown(int node) {
if (tree_nodes[node].lazy != -1) {
ll x = tree_nodes[node].lazy;
int left = 2 * node;
int l_start = tree_nodes[left].l;
int l_end = tree_nodes[left].r;
ll sum_c_left = safe(psc[l_end], psc[l_start - 1]);
tree_nodes[left].sum_a_c = (x % MOD) * sum_c_left % MOD;
tree_nodes[left].lazy = x;
int right = 2 * node + 1;
int r_start = tree_nodes[right].l;
int r_end = tree_nodes[right].r;
ll sum_c_right = safe(psc[r_end], psc[r_start - 1]);
tree_nodes[right].sum_a_c = (x % MOD) * sum_c_right % MOD;
tree_nodes[right].lazy = x;
tree_nodes[node].lazy = -1;
}
}
void getrange(int node, int l, int r, ll x) {
if (tree_nodes[node].l > r || tree_nodes[node].r < l)
return;
if (tree_nodes[node].l >= l && tree_nodes[node].r <= r) {
ll sum_c = safe(psc[tree_nodes[node].r],
psc[tree_nodes[node].l - 1]);
tree_nodes[node].sum_a_c = (x % MOD) * sum_c % MOD;
tree_nodes[node].lazy = x;
return;
}
pushdown(node);
getrange(2 * node, l, r, x);
getrange(2 * node + 1, l, r, x);
tree_nodes[node].sum_a_c =
(tree_nodes[2 * node].sum_a_c + tree_nodes[2 * node + 1].sum_a_c) % MOD;
}
ll query_sum(int node, int l, int r) {
if (tree_nodes[node].l > r || tree_nodes[node].r < l)
return 0;
if (tree_nodes[node].l >= l && tree_nodes[node].r <= r) {
return tree_nodes[node].sum_a_c;
}
pushdown(node);
ll res = (query_sum(2 * node, l, r) + query_sum(2 * node + 1, l, r)) % MOD;
return res;
}
int main() {
ios::sync_with_stdio(false);
cin.tie(0);
cin >> n >> m;
for (int i = 1; i <= n; i++)
cin >> a_init[i];
for (int i = 1; i <= n; i++) {
c[i] = (1LL * i * (n - i + 1)) % MOD;
}
psc[0] = 0;
for (int i = 1; i <= n; i++) {
psc[i] = (psc[i - 1] + c[i]) % MOD;
}
build(1, 1, n);
ll total = query_sum(1, 1, n);
cout << total % MOD << "\n";
for (int i = 0; i < m; i++) {
int l, r;
ll x;
cin >> l >> r >> x;
getrange(1, l, r, x % MOD);
total = query_sum(1, 1, n);
cout << total % MOD << "\n";
}
}

3
src/3/T225686.cpp Normal file
View File

@ -0,0 +1,3 @@
int main(){
}