Submission #1135825

#	Time	Username	Problem	Language	Result	Execution time	Memory
1135825		dombly	Divide and conquer (IZhO14_divide)	C++20	100 / 100	60 ms	14084 KiB

divide

#include <bits/stdc++.h>
#define int long long
#define F first
#define S second
#define pb push_back
using namespace std;
const int N = 200000 + 10;
const int inf = 1e15;
const int mod = 1e9 + 7;

int st[N * 4];

void build(int node,int tl,int tr) {
    st[node] = inf;
    if(tl == tr) return;
    int mid = (tl + tr) / 2;
    build(node * 2,tl,mid);
    build(node * 2 + 1,mid + 1,tr);
}

void modify(int node,int tl,int tr,int i,int v) {
    if(tl > i || tr < i) return;
    if(tl == tr) {
        st[node] = min(st[node],v);
        return;
    }
    int mid = (tl + tr) / 2;
    modify(node * 2,tl,mid,i,v);
    modify(node * 2 + 1,mid + 1,tr,i,v);
    st[node] = min(st[node * 2],st[node * 2 + 1]);
}

int get(int node,int tl,int tr,int l,int r) {
    if(tl > r || tr < l) return inf;
    if(tl >= l && tr <= r) return st[node];
    int mid = (tl + tr) / 2;
    return min(get(node * 2,tl,mid,l,r),get(node * 2 + 1,mid + 1,tr,l,r));
}

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

    int n;
    cin >> n;
    vector<int>x(n + 1),g(n + 1),e(n + 1),xs;
    vector<vector<int>>id(n + 1,vector<int>(2));
    for(int i = 1; i <= n; i++) {
        cin >> x[i] >> g[i] >> e[i];
        g[i] += g[i - 1];
        e[i] += e[i - 1];
        id[i][0] = e[i] - x[i];
        id[i][1] = e[i - 1] - x[i];
        xs.pb(e[i] - x[i]);
        xs.pb(e[i - 1] - x[i]);
    }
    sort(xs.begin(),xs.end());
    xs.erase(unique(xs.begin(),xs.end()),xs.end());
    for(int i = 1; i <= n; i++) {
        id[i][0] = lower_bound(xs.begin(),xs.end(),id[i][0]) - xs.begin() + 1;
        id[i][1] = lower_bound(xs.begin(),xs.end(),id[i][1]) - xs.begin() + 1;
    }
    build(1,1,n * 2);
    int res = 0;
    for(int i = 1; i <= n; i++) {
        modify(1,1,n * 2,id[i][1],g[i - 1]);
        res = max(res,g[i] - get(1,1,n * 2,1,id[i][0]));
    }
    //e[i]-x[i] >= e[j - 1] - x[j]
    cout << res;
    return 0;
}

• Subtask 1: 17 / 17
• Subtask 2: 31 / 31
• Subtask 3: 52 / 52