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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#182959#6737. Neighbourhooducup-team004#WA 5951ms199636kbC++205.8kb2023-09-18 19:39:022023-09-18 19:39:02

Judging History

This is the latest submission verdict.

  • [2023-09-18 19:39:02]
  • Judged
  • Verdict: WA
  • Time: 5951ms
  • Memory: 199636kb
  • [2023-09-18 19:39:02]
  • Submitted

answer

#include <bits/stdc++.h>

using i64 = long long;

constexpr int N = 2E5;
constexpr int LogN = 20;

int n, q;
int x[N], y[N], w[N];
std::vector<int> adj[N];

int cdep[N], cpar[N], siz[N];
int par[LogN][N], in[LogN][N], out[LogN][N], seq[LogN][N];
int st[LogN][N];
i64 A[LogN][N], B[LogN][N], tag[LogN][N];
bool vis[N];
int cur[LogN];
int blk[N + 1];

void dfs(int d, int x) {
    in[d][x] = cur[d]++;
    seq[d][in[d][x]] = x;
    siz[x] = 1;
    for (auto y : adj[x]) {
        if (vis[y] || y == par[d][x]) {
            continue;
        }
        par[d][y] = x;
        dfs(d, y);
        siz[x] += siz[y];
    }
    out[d][x] = cur[d];
}

int find(int x, int p, int s) {
    for (auto y : adj[x]) {
        if (vis[y] || y == p || 2 * siz[y] <= s) {
            continue;
        }
        return find(y, x, s);
    }
    return x;
}

int solve(int d, int r) {
    int t = cur[d];
    par[d][r] = -1;
    dfs(d, r);
    r = find(r, -1, siz[r]);
    par[d][r] = -1;
    cur[d] = t;
    dfs(d, r);
    cdep[r] = d;
    vis[r] = true;
    for (auto y : adj[r]) {
        if (vis[y]) {
            continue;
        }
        y = solve(d + 1, y);
        cpar[y] = r;
    }
    return r;
}

int lca(int u, int v) {
    if (u == v) {
        return u;
    }
    u = in[0][u];
    v = in[0][v];
    if (u > v) {
        std::swap(u, v);
    }
    int k = std::__lg(v - u);
    int a = st[k][u];
    int b = st[k][v - (1 << k)];
    return in[0][a] < in[0][b] ? a : b;
}

i64 getdep(int u) {
    int x = in[0][u];
    return A[0][x] + tag[0][x - x % blk[n]];
}

i64 dist(int u, int v) {
    int l = lca(u, v);
    return getdep(u) + getdep(v) - 2 * getdep(l);
}

void add(int d, int x, int l, int r, int c) {
    int L = in[d][x], R = out[d][x];
    int n = R - L;
    int b = blk[n];
    int lb = (l - L) / b;
    int rb = (r - 1 - L) / b;
    if (lb == rb) {
        for (int i = l; i < r; i++) {
            A[d][i] += c;
        }
        l = L + lb * b;
        r = std::min(R, l + b);
        std::copy(A[d] + l, A[d] + r, B[d] + l);
        std::sort(B[d] + l, B[d] + r);
    } else {
        for (int i = l; i < L + (lb + 1) * b; i++) {
            A[d][i] += c;
        }
        for (int i = lb + 1; i < rb; i++) {
            tag[d][L + i * b] += c;
        }
        for (int i = L + rb * b; i < r; i++) {
            A[d][i] += c;
        }
        l = L + lb * b;
        r = std::min(R, l + b);
        std::copy(A[d] + l, A[d] + r, B[d] + l);
        std::sort(B[d] + l, B[d] + r);
        l = L + rb * b;
        r = std::min(R, l + b);
        std::copy(A[d] + l, A[d] + r, B[d] + l);
        std::sort(B[d] + l, B[d] + r);
    }
}

int get(int d, int x, int l, int r, i64 v) {
    if (l == r) {
        return 0;
    }
    int L = in[d][x], R = out[d][x];
    int n = R - L;
    int b = blk[n];
    int lb = (l - L) / b;
    int rb = (r - 1 - L) / b;
    int res = 0;
    if (lb == rb) {
        i64 t = tag[d][L + lb * b];
        for (int i = l; i < r; i++) {
            res += (A[d][i] + t <= v);
        }
    } else {
        i64 t = tag[d][L + lb * b];
        for (int i = l; i < L + (lb + 1) * b; i++) {
            res += (A[d][i] + t <= v);
        }
        for (int i = lb + 1; i < rb; i++) {
            int l = L + i * b;
            int r = l + b;
            t = tag[d][l];
            res += std::upper_bound(B[d] + l, B[d] + r, v - t) - B[d] - l;
        }
        t = tag[d][L + rb * b];
        for (int i = L + rb * b; i < r; i++) {
            res += (A[d][i] + t <= v);
        }
    }
    return res;
}

void modify(int i, int c) {
    int X = x[i], Y = y[i];
    int u = X, v = Y;
    while (cdep[u] > cdep[v]) {
        u = cpar[u];
    }
    while (cdep[v] > cdep[u]) {
        v = cpar[v];
    }
    while (u != v) {
        u = cpar[u];
        v = cpar[v];
    }
    while (u != -1) {
        int d = cdep[u];
        int l = std::max(in[d][X], in[d][Y]);
        int r = std::min(out[d][X], out[d][Y]);
        add(d, u, l, r, c);
        u = cpar[u];
    }
}

int query(int x, i64 L) {
    int ans = 0;
    int y = -1;
    for (int i = x; i != -1; y = i, i = cpar[i]) {
        i64 dis = dist(x, i);
        int d = cdep[i];
        if (y != -1) {
            ans += get(d, i, in[d][i], in[d][y], L - dis);
            ans += get(d, i, out[d][y], out[d][i], L - dis);
        } else {
            ans += get(d, i, in[d][i], out[d][i], L - dis);
        }
    }
    return ans;
}

int main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    
    for (int i = 1; i <= N; i++) {
        blk[i] = std::sqrt(i);
    }
    
    std::cin >> n >> q;
    
    for (int i = 1; i < n; i++) {
        std::cin >> x[i] >> y[i] >> w[i];
        x[i]--, y[i]--;
        adj[x[i]].push_back(y[i]);
        adj[y[i]].push_back(x[i]);
    }
    cpar[solve(0, 0)] = -1;
    
    for (int i = 0; i < n; i++) {
        if (in[0][i] != 0) {
            st[0][in[0][i] - 1] = par[0][i];
        }
    }
    for (int k = 0; k + 1 < LogN; k++) {
        for (int i = 0; i + (2 << k) <= n - 1; i++) {
            int a = st[k][i];
            int b = st[k][i + (1 << k)];
            st[k + 1][i] = in[0][a] < in[0][b] ? a : b;
        }
    }
    
    for (int i = 1; i < n; i++) {
        modify(i, w[i]);
    }
    
    for (int _ = 0; _ < q; _++) {
        int o;
        std::cin >> o;
        
        if (o == 1) {
            int i, c;
            std::cin >> i >> c;
            modify(i, c - w[i]);
            w[i] = c;
        } else {
            int x;
            i64 d;
            std::cin >> x >> d;
            x--;
            std::cout << query(x, d) << "\n";
        }
    }
    
    return 0;
}

Details

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Test #1:

score: 100
Accepted
time: 0ms
memory: 32488kb

input:

3 7
1 2 3
2 3 1
2 2 1
2 1 3
2 3 4
1 1 1
2 2 1
2 1 0
2 3 1

output:

2
2
3
3
1
2

result:

ok 6 numbers

Test #2:

score: -100
Wrong Answer
time: 5951ms
memory: 199636kb

input:

200000 200000
1 2 146181238
2 3 45037818
3 4 176924060
4 5 969365276
5 6 683948619
6 7 356268194
7 8 871634797
8 9 630254480
9 10 283061123
10 11 204904965
11 12 838381393
12 13 516373812
13 14 253862710
14 15 223572474
15 16 114452997
16 17 145251056
17 18 905638436
18 19 375445402
19 20 549829545
...

output:

366
99349
2324
8635
107281
1153
19129
190278
8342
9341
4566
3814
29805
14084
36208
4877
178706
124397
259738
24200
32095
34336
14371
451
5924
5328
10844
57956
8537
251589
22736
153
1447
182
103963
1509
17583
2903
52322
1599
8076
17001
36208
359
61943
3910
23430
3562
66996
136632
130821
7386
123939
2...

result:

wrong answer 1st numbers differ - expected: '219', found: '366'