제출 #497409

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
497409		Ierus	Bigger segments (IZhO19_segments)	C++17	0 / 100	1 ms	312 KiB

segments

#include<bits/stdc++.h>
using namespace std;
#pragma GCC optimize ("unroll-loops,Ofast,O3")
#pragma GCC target("avx,avx2,fma")
#define F first
#define S second
#define int long long
#define sz(x) (int)x.size()
#define pb push_back
#define eb emplace_back
#define all(x) (x).begin(),(x).end()
//const int E = 5e5+777;
//const long long inf = 1e18+777;
//const int N = 3e3+777;
//const int MOD = 1e9+7;
int getfast(vector<int> v){
	int n = sz(v);
	int pref[n+2]{}, a[n+2]{};
	for(int i = 0; i < n; ++i) a[i+1] = v[i];
	for(int i = 1; i <= n; ++i) pref[i] = pref[i-1] + a[i];
    auto get = [&](int l, int r){
    	if(l == -1 || r == -1) return -(int)1e9;
    	return pref[r] - pref[l-1];
	};
	int ans = 1, last = a[1];
    for(int i = 2; i <= n; ++i){
    	int L = i, R = n, res = -1;
    	while(L <= R){
    		int M = (L + R) >> 1LL;
    		if(last <= get(i, M)){
    			R = (res = M) - 1;
    		}else L = M + 1;
    	}
    	if(last <= get(i, res)){
    		++ans;
    	}else break;
    	int k = i;
    	for(; k < res; ++k){
//    		cerr << "k: " << k << " last+k: " << last + k << " get(k+1,res): " << get(k+1,res) << '\n';
    		if(last + a[k] <= get(k+1, res)){
    			last += a[k];
    		}else break;
    	}
//    	cerr << "i: " << i << " ans: " << get(k, res) << " l: " << k << " r: " << res << '\n';
    	last = get(k, res);
//    	cerr << "last: " << last << '\n';
    	i = res;
    }
	return ans;
}
signed main(){
    ios_base::sync_with_stdio(0),
    cin.tie(0),cout.tie(0);
	int n; cin >> n;
	vector<int> a(n);
	for(auto &i : a) cin >> i;
	cout << getfast(a);
}

• Subtask 1: 0 / 13
• Subtask 2: 0 / 14
• Subtask 3: 0 / 10
• Subtask 4: 0 / 36
• Subtask 5: 0 / 27