Submission #934535

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
934535	2024-02-27T14:25:36 Z	GrindMachine	The Big Prize (IOI17_prize)	C++17	20 / 100	52 ms	3532 KB

prize

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x, y) ((x + y - 1) / (y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl

#define rep(i, n) for(int i = 0; i < n; ++i)
#define rep1(i, n) for(int i = 1; i <= n; ++i)
#define rev(i, s, e) for(int i = s; i >= e; --i)
#define trav(i, a) for(auto &i : a)

template<typename T>
void amin(T &a, T b) {
    a = min(a, b);
}

template<typename T>
void amax(T &a, T b) {
    a = max(a, b);
}

#ifdef LOCAL
#include "debug.h"
#else
#define debug(x) 42
#endif

/*

refs:
edi
https://codeforces.com/blog/entry/53595?#comment-376650

f(i+1) > f(i)^2
#of non-lollipops = O(sqrt(n))

just check all non-lollipops for diamond
efficiently find all non-lollipops

*/

const int MOD = 1e9 + 7;
const int N = 2e5 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;
const int B = 455;

#include "prize.h"

vector<pii> dp(N,{-1,-1});
int q = 0;

pii ask2(int i){
	if(dp[i].ff != -1) return dp[i];
	q++;
	assert(q <= 1e4);
	vector<int> v = ask(i);
	return dp[i] = {v[0],v[1]};
}

int find_best(int n) {
	int mx = -1, pos = -1;

	rep(i,2){
		auto [cl,cr] = ask2(i);
		int cnt = cl+cr;
		if(cnt == 0){
			return i;
		}

		if(cnt > mx){
			mx = cnt;
			pos = i;
		}
	}

	assert(pos != -1);

	deque<int> dq;
	for(int i = pos+B; i < n; i += B){
		dq.pb(i);
	}

	trav(i,dq){
		ask2(i);
	}

	// find the closest non-lollipop with ind > i
	// given that the curr pos is a lollipop
	while(pos < n-1){
		while(!dq.empty() and dq.front() <= pos){
			dq.pop_front();
		}

		auto [fcl,fcr] = ask2(pos);
		int l = pos+1, r = n-1;

		if(!dq.empty()){
			l = dq.back()+1;
			rep(i,sz(dq)){
				auto [cl,cr] = ask2(dq[i]);
				int cnt = cl+cr;
				bool ok = false;

				// mid is not a lollipop
				if(cnt != mx){
					ok = true;
				}
				else{
					// mid is a lollipop
					if(cl > fcl){
						ok = true;
					}
				}

				if(ok){
					if(!i){
						l = pos+1;
					}
					else{
						l = dq[i-1]+1;
					}

					r = dq[i];
					break;
				}
			}	
		}

		int first = -1;

		while(l <= r){
			// is there a lollipop in range [pos,mid]?
			int mid = (l+r) >> 1;
			auto [cl,cr] = ask2(mid);
			int cnt = cl+cr;
			bool ok = false;

			// mid is not a lollipop
			if(cnt != mx){
				ok = true;
			}
			else{
				// mid is a lollipop
				if(cl > fcl){
					ok = true;
				}
			}

			if(ok){
				first = mid;
				r = mid-1;
			}
			else{
				l = mid+1;
			}
		}

		if(first == -1){
			break;
		}

		pos = -1;

		// find the closest pos >= first that is a lollipop
		for(int i = first; i < n; ++i){
			auto [cl,cr] = ask2(i);
			int cnt = cl+cr;
			
			if(cnt == 0){
				return i;
			}

			if(cnt == mx){
				pos = i;
				break;
			}
		}

		if(pos == -1) break;
	}

	// assert(0);
	return -1;
}

Compilation message

prize.cpp: In function 'int find_best(int)':
prize.cpp:28:36: warning: comparison of integer expressions of different signedness: 'int' and 'std::deque<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   28 | #define rep(i, n) for(int i = 0; i < n; ++i)
      |                                    ^
prize.cpp:121:4: note: in expansion of macro 'rep'
  121 |    rep(i,sz(dq)){
      |    ^~~

Subtask #1

20.0 / 20.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	3 ms	2016 KB	Output is correct
2	Correct	2 ms	2016 KB	Output is correct
3	Correct	2 ms	2016 KB	Output is correct
4	Correct	2 ms	2008 KB	Output is correct
5	Correct	2 ms	2012 KB	Output is correct
6	Correct	1 ms	1880 KB	Output is correct
7	Correct	3 ms	2012 KB	Output is correct
8	Correct	3 ms	2016 KB	Output is correct
9	Correct	3 ms	2016 KB	Output is correct
10	Correct	3 ms	2020 KB	Output is correct

Subtask #2

0 / 80.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	4 ms	2016 KB	Output is correct
2	Correct	3 ms	2012 KB	Output is correct
3	Correct	3 ms	2016 KB	Output is correct
4	Correct	2 ms	2012 KB	Output is correct
5	Correct	3 ms	2016 KB	Output is correct
6	Correct	1 ms	1880 KB	Output is correct
7	Correct	2 ms	2016 KB	Output is correct
8	Correct	3 ms	2016 KB	Output is correct
9	Correct	4 ms	2012 KB	Output is correct
10	Correct	3 ms	2008 KB	Output is correct
11	Correct	3 ms	2012 KB	Output is correct
12	Correct	3 ms	2012 KB	Output is correct
13	Correct	4 ms	2016 KB	Output is correct
14	Correct	2 ms	1880 KB	Output is correct
15	Correct	5 ms	2016 KB	Output is correct
16	Correct	21 ms	2020 KB	Output is correct
17	Correct	3 ms	2012 KB	Output is correct
18	Correct	16 ms	2012 KB	Output is correct
19	Correct	3 ms	2012 KB	Output is correct
20	Correct	5 ms	2132 KB	Output is correct
21	Correct	10 ms	2012 KB	Output is correct
22	Correct	4 ms	2020 KB	Output is correct
23	Correct	3 ms	2008 KB	Output is correct
24	Correct	3 ms	2144 KB	Output is correct
25	Correct	15 ms	2020 KB	Output is correct
26	Correct	13 ms	2016 KB	Output is correct
27	Correct	3 ms	2012 KB	Output is correct
28	Correct	21 ms	2180 KB	Output is correct
29	Correct	14 ms	2016 KB	Output is correct
30	Correct	20 ms	2012 KB	Output is correct
31	Correct	3 ms	2008 KB	Output is correct
32	Correct	4 ms	2020 KB	Output is correct
33	Correct	1 ms	1880 KB	Output is correct
34	Correct	9 ms	2020 KB	Output is correct
35	Correct	3 ms	2016 KB	Output is correct
36	Correct	7 ms	2012 KB	Output is correct
37	Correct	3 ms	2020 KB	Output is correct
38	Correct	3 ms	2016 KB	Output is correct
39	Correct	11 ms	2016 KB	Output is correct
40	Correct	20 ms	2016 KB	Output is correct
41	Correct	16 ms	2016 KB	Output is correct
42	Correct	14 ms	2012 KB	Output is correct
43	Correct	11 ms	2016 KB	Output is correct
44	Correct	9 ms	2016 KB	Output is correct
45	Correct	8 ms	2012 KB	Output is correct
46	Correct	2 ms	2016 KB	Output is correct
47	Correct	11 ms	2012 KB	Output is correct
48	Correct	13 ms	2008 KB	Output is correct
49	Correct	5 ms	2016 KB	Output is correct
50	Correct	23 ms	2012 KB	Output is correct
51	Correct	9 ms	2012 KB	Output is correct
52	Correct	3 ms	2020 KB	Output is correct
53	Correct	3 ms	2016 KB	Output is correct
54	Correct	9 ms	2008 KB	Output is correct
55	Correct	3 ms	2016 KB	Output is correct
56	Correct	22 ms	2008 KB	Output is correct
57	Correct	15 ms	2020 KB	Output is correct
58	Correct	18 ms	2012 KB	Output is correct
59	Correct	13 ms	2016 KB	Output is correct
60	Correct	16 ms	2020 KB	Output is correct
61	Correct	3 ms	2016 KB	Output is correct
62	Correct	3 ms	2008 KB	Output is correct
63	Correct	3 ms	2012 KB	Output is correct
64	Correct	3 ms	2012 KB	Output is correct
65	Runtime error	52 ms	3532 KB	Execution killed with signal 6
66	Halted	0 ms	0 KB	-