Submission #366865

#	Time	Username	Problem	Language	Result	Execution time	Memory
366865		kostia244	Archery (IOI09_archery)	C++17	20 / 100	2090 ms	620 KiB

archery

#pragma GCC optimize("Ofast,unroll-loops")
#pragma GCC target("avx,avx2,sse,sse2")
#include<bits/stdc++.h>
using namespace std;
using ll = long long;
#define all(x) begin(x), end(x)
const int maxn = 4002;
int n, r, p = 0, a[maxn], sp = 0;
char cur[maxn];
array<int, 2> ans = {100000, -1};
void check() {
	for(int i = 0; i < n; i++) cur[i] = a[i];
	//for(int i = 0; i < n; i++) cout << cur[i] << " "; cout << endl;
	for(int it = 0; it < r; it++) {
		#pragma GCC ivdep
		for(int i = 1; i < n; i += 2) if(cur[i] < cur[i-1]) {
			cur[i] ^= cur[i-1];
			cur[i-1] ^= cur[i];
			cur[i] ^= cur[i-1];
		}
		int FF = cur[1];
		#pragma GCC ivdep
		for(int i = 1; i+1 < n; i++) cur[i] = cur[i+1];
		cur[n-1] = FF;
	}
	int pos = 0;
	while(cur[pos]) pos++;
	ans = min(ans, {pos, -sp});
}
int main() {
	cin.tie(0)->sync_with_stdio(0);
	cin >> n >> r;
	n *= 2;
	r = r%(2*n);
	r += 2*n;
	cin >> p;
	for(int i = 1; i < n; i++) {
		cin >> a[i];
	}
	for(int i = 1; i < n; i++) {
		a[i] = a[i] < p ? -1 : 1;
	}
	check();
	for(int i = 1; i < n; i++) {
		swap(a[i], a[i-1]);
		sp++;
		check();
	}
	cout << 1 + ((-ans[1])/2) << '\n';
} 

• Subtask 1: 4 / 6
• Subtask 2: 16 / 94