Submission #924240

#	Time	Username	Problem	Language	Result	Execution time	Memory
924240		DAleksa	Two Currencies (JOI23_currencies)	C++17	0 / 100	8 ms	47000 KiB

currencies

// todo

#include <bits/stdc++.h>

using namespace std;

struct node {
    int cnt;
    long long sum;
    node() : cnt(0), sum(0) { }
};

const int N = 1e5 + 10, LOG = 18;
int n, m, q;
vector<int> g[N];
vector<pair<int, pair<int, int>>> edges;
int tin[N], tout[N], timer;
int up[N][LOG];
node st[25 * N];
int ll[25 * N], rr[25 * N];
int id;
int dep[N];

bool is_ancestor(int u, int v) { return tin[u] <= tin[v] && tout[u] >= tout[v]; }

int LCA(int u, int v) {
    if(is_ancestor(u, v)) return u;
    if(is_ancestor(v, u)) return v;
    for(int j = LOG - 1; j >= 0; j--) {
        if(up[u][j] == 0) continue;
        if(is_ancestor(up[u][j], v)) continue;
        u = up[u][j];
    }
    return up[u][0];
}

void dfs(int u, int par) {
    tin[u] = ++timer;
    for(int v : g[u]) {
        if(v == par) continue;
        up[v][0] = u;
        dep[v] = dep[u] + 1;
        dfs(v, u);
    }
    tout[u] = timer;
}

void update(int root, int oldroot, int l, int r, int x, int val1, long long val2) {
    if(l > r || r < x || x < l) return;
    if(l == r) {
        st[root].cnt += val1;
        st[root].sum += val2;
        return;
    }
    int mid = (l + r) / 2;
    if(mid >= x) {
        ll[root] = ++id;
        rr[root] = rr[oldroot];
        update(ll[root], ll[oldroot], l, mid, x, val1, val2);
    } else {
        ll[root] = ll[oldroot];
        rr[root] = ++id;
        update(rr[root], rr[oldroot], mid + 1, r, x, val1, val2);
    }
    st[root].cnt = st[ll[root]].cnt + st[rr[root]].cnt;
    st[root].sum = st[ll[root]].sum + st[rr[root]].sum;
}

node get(int root, int l, int r, int L, int R) {
    if(l > r || r < L || R < l) return node();
    if(L <= l && r <= R) return st[root];
    int mid = (l + r) / 2;
    node nd1 = get(ll[root], l, mid, L, R);
    node nd2 = get(rr[root], mid + 1, r, L, R);
    node nd;
    nd.cnt = nd1.cnt + nd2.cnt;
    nd.sum = nd1.sum + nd2.sum;
    return nd;
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cin >> n >> m >> q;
    for(int i = 1; i < n; i++) {
        int u, v;
        cin >> u >> v;
        g[u].push_back(v);
        g[v].push_back(u);
        edges.push_back({0, {u, v}});
    }
    for(int i = 0; i < m; i++) {
        int ind, val;
        cin >> ind >> val;
        edges[ind - 1].first = val;
    }
    sort(edges.begin(), edges.end());
    dfs(1, 0);
    for(int j = 1; j < LOG; j++) for(int i = 1; i <= n; i++) up[i][j] = up[up[i][j - 1]][j - 1];
    for(int i = 0; i < edges.size(); i++) {
        pair<int, pair<int, int>> e = edges[i];
        int u = e.second.first, v = e.second.second;
        if(up[v][0] == u) swap(u, v);
        int w = e.first;
        id++;
        update(id, id - 1, 1, n, tin[u], 1, w);
        if(tout[u] < n) update(id, id - 1, 1, n, tout[u] + 1, -1, -w);
    }
    while(q--) {
        int u, v, x;
        long long y;
        cin >> u >> v >> x >> y;
        int lca = LCA(u, v);
        int l = 0, r = edges.size() - 1;
        int ans = l;
        while(l <= r) {
            int mid = (l + r) / 2;
            if(get(mid + 1, 1, n, 1, tin[u]).sum + get(mid + 1, 1, n, 1, tin[v]).sum - 2 * get(mid + 1, 1, n, 1, tin[lca]).sum <= y) {
                ans = mid;
                l = mid + 1;
            } else r = mid - 1;
        }
        cout << dep[u] + dep[v] - 2 * dep[lca] - (get(ans + 1, 1, n, 1, tin[u]).sum + get(ans + 1, 1, n, 1, tin[v]).sum - 2 * get(ans + 1, 1, n, 1, tin[lca]).sum) << "\n";
    }
    return 0;
}

Compilation message (stderr)

currencies.cpp: In function 'int main()':
currencies.cpp:100:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, std::pair<int, int> > >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  100 |     for(int i = 0; i < edges.size(); i++) {
      |                    ~~^~~~~~~~~~~~~~

• Subtask 1: 0 / 10
• Subtask 2: 0 / 28
• Subtask 3: 0 / 30
• Subtask 4: 0 / 32