Submission #1162247

#	Time	Username	Problem	Language	Result	Execution time	Memory
1162247		arkanefury	Divide and conquer (IZhO14_divide)	C++20	100 / 100	27 ms	5364 KiB

divide

#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define in insert
#define lb lower_bound
#define F first
#define S second
#define sz size()
#define int long long
#define all(v) v.begin(),v.end()
#define FOR1(x, n) for(int j = x; j <= n; j ++)
#define FOR(x, n, m, d) for(int x = n; x <= m; x += d)
#define FORR(x, n, m, d) for(int x = n; x >= m; x -= d)
#define nikita ios_base::sync_with_stdio(0), cin.tie(0);
const int N =  5e5+5;
int a[N], b[N], pref[N], d[N], c[N], ans, e[N], pref1[N];
int n,m,sum=0,x,y, r, cnt, l, mod = 998244353, inf = -1e18, k;
string s, str;
void dnc(int l = 1, int r = n){
    if(l==r)ans = max(ans, b[l]);
    if(l >= r)return;
    int md = (l+r) >> 1;
    dnc(l, md), dnc(md+1, r);
    vector<int>v;
    int prefix = 0, prefix1 = 0;
    FORR(i, r, md+1, 1){
        prefix = pref[i] - pref[md];
        v.pb(a[i]-prefix);
    }
    int mn = 1e18;
    FOR(i,0,v.sz-1,1){
        mn=min(mn,v[i]);
        d[i]=mn;
    }
    prefix = prefix1 = 0;
    FORR(i, md, l, 1){
        prefix += c[i];
        prefix1 += b[i];
        int tl, tr, tm;
        tl = 0, tr = v.sz-1;
        k = a[i] + prefix;
        int res = -1;
        while(tl <= tr){
            tm = (tl + tr) >> 1;
            if(d[tm] <= k)tr = tm - 1, res = tm;
            else tl = tm + 1;
        }
        if(res!=-1){
            res = r-res;
        ans = max( pref1[res] - pref1[i-1], ans);
        }
    }
}
// pref[j] + suf[i] >= a[j] - a[i]
// a[j] - pref[j] <= a[i] + suf[i]
void solve(){
    cin >> n;
    FOR(i,1,n,1){
        cin>>a[i]>>b[i]>>c[i];
        pref1[i] = pref1[i-1] + b[i];
        pref[i] = pref[i-1] + c[i];
    }
    dnc();
    cout << ans;
}
signed main(){
    nikita
    int tt = 1;
    if(!tt)cin >> tt;
    FOR(i, 1, tt, 1){
        solve();
    }
}

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