Submission #242904

#	Time	Username	Problem	Language	Result	Execution time	Memory
242904		MatesV13	Svjetlost (COI18_svjetlost)	C++11	40 / 100	3031 ms	6136 KiB

Main

#include <bits/stdc++.h>
using namespace std;
long long n, q, V, x[100005], y[100005], prijasnji[100005];
void update(int vrh){
	int minus=0;
	for (int i=1; i<vrh; i++){
		if (prijasnji[i]) minus++;
	} prijasnji[vrh]++; vrh-=minus;
	for (int i=vrh+1; i<=n; i++){
		x[i-1]=x[i]; y[i-1]=y[i];
	} return;
}
bool ok (int idx1, int idx2){
	idx1 = (idx1+n-1)%n+1; idx2 = (idx2+n-1)%n+1;
	long long dx1 = x[idx1] - x[idx1-1];
	long long dy1 = y[idx1] - y[idx1-1];
	long long dx2 = x[idx2] - x[idx2-1];
	long long dy2 = y[idx2] - y[idx2-1];
//	cout << dx1 << " " << dy1 << "   " << dx2 << " " << dy2 << endl;
//	cout << dx1*dy2 << " " << dx2*dy1 << endl;
	return (dx1*dy2 > dx2*dy1);
}
long double leng(int idx){
	idx = (idx+n-1)%n+1;
	long long dx = x[idx] - x[idx-1];
	long long dy = y[idx] - y[idx-1];
//	cout << "duljina izmedu " << idx << " i " << idx-1 << " iznosi: " << sqrtl(dx*dx + dy*dy) << endl;
	return sqrtl(dx*dx + dy*dy);
}
long double dp[200005];
void check(){
	long double ans=0.0000000000;
	x[0]=x[n]; y[0]=y[n];
	int cur=1; dp[1] = leng(1); ans=dp[1];
//	cout << "pomoc: 1 1" << endl << "udaljenost: " << dp[1] << endl << "ans: " << ans << endl << endl;
	for (int i=2; i<=2*n; i++){
		while (!ok(cur, i)) cur++;
//		cout << "pomoc: " << i << " " << cur << endl;
		dp[i] = dp[i-1] + leng(i);
//		cout << "udaljenost: " << dp[i] << endl;
		ans = max(ans, dp[i] - dp[cur-1]);
//		cout << "ans: " << ans << endl << endl;
	} cout << ans << endl; return;
}
int main (){
ios::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
cin >> n; 
for (int i=1; i<=n; i++){
	cin >> x[i] >> y[i];
}
cout << fixed << setprecision(10);
check(); cin >> q;
while (q--){
	cin >> V; update(V); n--; check();
}
return 0;
}

• Subtask 1: 12 / 12
• Subtask 2: 14 / 14
• Subtask 3: 14 / 14
• Subtask 4: 0 / 29
• Subtask 5: 0 / 31