Submission #1023413

#	Time	Username	Problem	Language	Result	Execution time	Memory
1023413		armashka	Fountain (eJOI20_fountain)	C++17	100 / 100	218 ms	41132 KiB

fountain

#include<bits/stdc++.h>

// #pragma GCC target("avx2")
// #pragma GCC optimize("Ofast")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")

using namespace std;

#define fast ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define file(s) freopen(s".in", "r", stdin);freopen(s".out", "w", stdout);
#define all(v) v.begin(),v.end()
#define rall(v) v.rbegin(),v.rend()
#define pb push_back
#define pf push_front
#define ppb pop_back
#define ft first
#define sd second
#define ll long long
#define ull unsigned ll
#define pii pair<int,int>
#define pll pair<ll,ll>
const int N = 3e5 + 10;
const int M = 1e6 + 5;
const int B = 316;
const ll msize = 2;
const ll mod1 = 1e9 + 7;
const ll mod2 = 998244353;
const long double Phi = acos(-1);
const long long inf = 2e18;
const vector <pair<int, int>> dir = {{-1, 0}, {1, 0}, {0, -1}, {0, 1}};

ll binmul(ll x, ll ti, ll m);
ll binpow(ll x, ll ti, ll m);

ll n, q, d[N], c[N];
vector <int> g[N];
ll pref[N], up[N][19];

void dfs(int v, int pr) {
    up[v][0] = pr;
    pref[v] += c[v];

    for (int i = 1; i <= 18; ++ i) {
        up[v][i] = up[up[v][i - 1]][i - 1];
    }

    for (auto to : g[v]) {
        if (to != pr) {
            pref[to] = pref[v];
            dfs(to, v);
        }
    }
}

int get(int u, ll x) {
    if (c[u] >= x) return u;
    int cur = u;
    for (int i = 18; i >= 0; -- i) {
        int v = up[u][i];
        if (pref[cur] - pref[v] + c[v] < x) u = v; 
    }
    int ans = up[u][0];
    return (ans == n + 1 ? 0 : ans);
}

const void solve() {
    cin >> n >> q;
    for (int i = 1; i <= n; ++ i) {
        cin >> d[i] >> c[i];
    }

    c[n + 1] = d[n + 1] = 1e9+1;
    stack<int> st;
    st.push(n + 1);

    for (int i = n; i >= 1; -- i) {
        while (st.size() && d[st.top()] <= d[i]) st.pop();

        int j = st.top();
        g[j].pb(i);
        
        st.push(i);
    }

    dfs(n + 1, n + 1);

    for (int i = 1; i <= q; ++ i) {
        ll u, x;
        cin >> u >> x;
        cout << get(u, x) << "\n";
    }
} 

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    srand(time(NULL));

    // file("promote");

    // freopen("input.txt", "r", stdin);
    // freopen("output.txt", "w", stdout);

    int tt = 1;
    // cin >> tt;
    for (int i = 1; i <= tt; ++ i) {
        // cout << "Caso #" << i << "\n";
        solve();
    }

    #ifndef ONLINE_JUDGE
    cerr << "\n" << 1.0 * clock() / CLOCKS_PER_SEC << " s.\n";
    #endif

    return 0;
} 


// Template functions
ll binmul(ll x, ll ti, ll m) { ll res = 0;while (ti){if(ti & 1)res += x;x += x;ti >>= 1; x %= m; res %= m;} return res;}
ll binpow(ll x, ll ti, ll m) { ll res = 1;while (ti){if(ti & 1)(res *= x)%=m;(x*=x)%=m;ti >>= 1; x %= m; res %= m;} return res;}
   

• Subtask 1: 30 / 30
• Subtask 2: 30 / 30
• Subtask 3: 40 / 40