Submission #803029

#	Time	Username	Problem	Language	Result	Execution time	Memory
803029		lukameladze	Two Currencies (JOI23_currencies)	C++17	0 / 100	10 ms	8648 KiB

currencies

# include <bits/stdc++.h>
using namespace std;
#define f first
#define s second
#define pii pair <int, int>
#define pb push_back
const int N = 3e5 + 5;
int n, m, q, a[N], b[N], edge[N], par[N][20], idx[N], c[N], in[N], out[N], tin, cur;
vector <pii> v[N];
int le_[30 * N], ri_[30 * N], root[N]; 
pii tree[30 * N];
void dfs(int a, int p) {
    par[a][0] = p;
    for (int i = 1; i <= 18; i++) {
        par[a][i] = par[par[a][i - 1]][i - 1];
    }
    in[a] = ++tin;
    for (pii sth : v[a]) {
        int to = sth.f, id = sth.s;
        if (to == p) continue;
        edge[id] = to; // {a, to}
        dfs(to, a);
    }
    out[a] = tin;
}
int upper(int a, int b) {
    return (in[a] <= in[b] && out[a] >= out[b]);
}
int lca(int a, int b) {
    if (upper(a, b)) return a;
    for (int i = 18; i >= 0; i--) {
        if (par[a][i] && !upper(par[a][i], b)) a = par[a][i];
    }
    return par[a][0];
}
pii merge(pii a, pii b) {
    return {a.f + b.f, a.s + b.s};
}
void build(int node, int le, int ri) {
    if (le == ri) {
        tree[node] = {0, 0};
        return ;
    }
    int mid = (le + ri) / 2;
    le_[node] = ++cur; ri_[node] = ++cur;
    build(le_[node], le, mid);
    build(ri_[node], mid + 1, ri);
    tree[node] = merge(tree[le_[node]], tree[ri_[node]]);
}
void update(int node, int le, int ri, int idx, int val) {
    if (le > idx || ri < idx) return ;
    if (le == ri) {
        tree[cur] = {tree[node].f + val, tree[node].s + ((val > 0) ? 1 : -1)};
        return ;
    }
    int mid = (le + ri) / 2;
    int x = cur;
    le_[x] = le_[node]; ri_[x] = ri_[node];
    if (idx <= mid) le_[x] = ++cur;
    else ri_[x] = ++cur;
    update(le_[node], le, mid, idx, val); // node
    update(ri_[node], mid + 1, ri, idx, val); //node
    tree[x] = merge(tree[le_[x]], tree[ri_[x]]);
}
pii getans(int node, int le, int ri, int start, int end) {
    if (le > end || ri < start) return {0, 0};
    if (le >= start && ri <= end) return tree[node];
    int mid = (le + ri) / 2;
    return merge(getans(le_[node], le, mid, start, end), getans(ri_[node], mid + 1, ri, start, end));
}
signed main() {
    cin>>n>>m>>q;
    for (int i = 1; i <= n - 1; i++) {
        cin>>a[i]>>b[i];
        v[a[i]].pb({b[i], i}); v[b[i]].pb({a[i], i});
    }
    dfs(1, 0);
    vector <pii> vec;
    for (int i = 1; i <= m; i++) {
        cin>>idx[i]>>c[i];
        idx[i] = edge[idx[i]]; // {a, to}
        vec.pb({c[i], idx[i]});
    }
    vec.pb({0, 0});
    sort(vec.begin(), vec.end());
    root[0] = 1; cur = 1;
    build(1, 1, n);
    for (int i = 1; i < (int)vec.size(); i++) {
        root[i] = ++cur;
        //cout<<"update "<<in[vec[i].s]<<" "<<out[vec[i].s]<<" "<<vec[i].f<<"\n";
        update(root[i - 1], 1, n, in[vec[i].s], vec[i].f);
        int proot = root[i];
        if (out[vec[i].s] + 1 <= n) {
            root[i] = ++cur;
            update(proot, 1, n, out[vec[i].s] + 1, -vec[i].f);
        }
        /*
        for (int j = 1; j <= n; j++) {
            cout<<getans(root[i], 1, n, 1, in[j]).s<<" ";
        }
        cout<<"\n";
        */
    }
    while (q--) {
        int s, t, x, y;
        cin>>s>>t>>x>>y;  int lc = lca(s, t);
        int l = 0, r = (int)vec.size() - 1, ans = -1;
        while (l <= r) {
            int mid = (l + r) / 2;
            int silver = getans(root[mid], 1, n, 1, in[s]).f + getans(root[mid], 1, n, 1, in[t]).f - 2 * getans(root[mid], 1, n, 1, in[lc]).f;
            if (silver <= y) {
                ans = mid; l = mid + 1;
            } else r = mid - 1;
        }
        if (ans == (int)vec.size() - 1) {
            cout<<x<<"\n"; continue;
        }
        int sz = (int)vec.size() - 1;
        int rem = getans(root[sz], 1, n, 1, in[s]).s + getans(root[sz], 1, n, 1, in[t]).s - 2 * getans(root[sz], 1,n, 1, in[lc]).s;
        rem -= (getans(root[ans], 1, n, 1, in[s]).s + getans(root[ans], 1, n, 1, in[t]).s - 2 * getans(root[ans], 1, n, 1, in[lc]).s);
        if (rem > x) cout<<-1<<"\n";
        else cout<<(x - rem)<<"\n"; 
    }
}

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