Submission #1224539

#	Time	Username	Problem	Language	Result	Execution time	Memory
1224539		ByeWorld	Finding Routers (IOI20_routers)	C++20	70.48 / 100	2 ms	328 KiB

routers

#include "routers.h"
#include <bits/stdc++.h>
#define us use_detector
#define ll long long
#define se second
#define fi first
#define pb push_back
#define lf (id<<1)
#define rg ((id<<1)|1)
#define md ((l+r)>>1)
using namespace std;

void chmn(auto &a, auto b){ a = min(a, b); }
void chmx(auto &a, auto b){ a = max(a, b); }

int n, ma;
int a[1010], dis[1010]; // i ke i-1

void find(int idx){
	int mx = 0, mn = ma;
	for(int i=0; i<=idx-1; i++) chmx(mx, a[i]);
	for(int i=idx+1; i<=n-1; i++) 
		if(a[i] != -1) chmn(mn, a[i]);

	int l=mx+1, r=mn, mid=0, cnt=-1;
	while(l<=r){
		mid = md;
		int ret = us(mid);
		if(ret < idx) cnt = mid, l = mid+1;
		else r = mid-1;
	}
	dis[idx] = 2*cnt;
}

std::vector<int> find_routers(int MA, int N, int q) {
	n = N; ma = MA;
	for(int i=1; i<=n-1; i++) a[i] = -1;

	if(n/2 != 0){
		find(n/2);
		for(int i=n/2+1; i<=n-1; i++) find(i);
		for(int i=n/2-1; i>=1; i--) find(i);
	} else {
		for(int i=1; i<=n-1; i++) find(i);
	}
	vector<int> ans; ans.pb(0);
	for(int i=1; i<=n-1; i++){
		a[i] = dis[i]-a[i-1];
		// cout << a[i] << " a\n";
		ans.pb(a[i]);
		assert(a[i] != -1);
	}
	// for(auto in : ans) cout << in << " in\n";
	return ans;
}

• Subtask 1: 16 / 16
• Subtask 2: 21 / 21
• Subtask 3: 23 / 23
• Subtask 4: 10.4768 / 40