Submission #911992

#	Time	Username	Problem	Language	Result	Execution time	Memory
911992		dsyz	Coreputer (IOI23_coreputer)	C++17	80 / 100	1 ms	808 KiB

coreputer

#include <bits/stdc++.h>
#include "coreputer.h"
using namespace std;
using ll = long long;
#define MAXN (1000005)

vector<int> malfunctioning_cores(int N) {
	ll high = N - 1;
	ll low = -1;
	while(high - low > 1){ //binary search for leftmost position such that prefix sum of malfunctioning cores > half of total malfunctioning cores
		ll mid = (high + low) / 2;
		vector<int> T;
		for(ll i = 0;i <= mid;i++){
			T.push_back(i);
		}
		ll a = run_diagnostic(T);
		if(a == 1){
			high = mid;
		}else{
			low = mid;
		}
	}
	ll checked = 1;
	ll parity = 0; //parity of total number of malfunctioning cores
	vector<ll> malfunctioning;
	malfunctioning.push_back(high);
	for(ll i = 0;i < high;i++){
		vector<int> T;
		for(ll j = 0;j <= high;j++){
			if(i == j) continue;
			T.push_back(j);
		}
		ll a = run_diagnostic(T);
		if(a == 0){
			parity = 0;
			malfunctioning.push_back(i);
		}else if(a == -1){
			parity = 1;
			malfunctioning.push_back(i);
		}
		checked++;
	}
	for(ll i = high + 1;i < N && malfunctioning.size() >= 2;i++){
		vector<int> T;
		for(ll j = high;j < N;j++){
			if(i == j) continue;
			T.push_back(j);
		}
		ll a = run_diagnostic(T);
		if(a == -1){
			malfunctioning.push_back(i);
		}
		checked++;
	}
	vector<int> ans;
	for(ll i = 0;i < N;i++){
		ans.push_back(0);
	}
	for(auto u : malfunctioning){
		ans[u] = 1;
	}
	return ans;
}

Compilation message (stderr)

coreputer.cpp: In function 'std::vector<int> malfunctioning_cores(int)':
coreputer.cpp:24:5: warning: variable 'parity' set but not used [-Wunused-but-set-variable]
   24 |  ll parity = 0; //parity of total number of malfunctioning cores
      |     ^~~~~~

• Subtask 1: 20 / 20
• Subtask 2: 30 / 40
• Subtask 3: 30 / 40