Submission #907226

#	Time	Username	Problem	Language	Result	Execution time	Memory
907226		daoquanglinh2007	Simple game (IZhO17_game)	C++17	100 / 100	46 ms	7000 KiB

game

#include <bits/stdc++.h>
using namespace std;

const int NM = 1e5, LIM = 1e6;

int N, M, a[NM+5];
int bit[LIM+5];

void update(int x, int val){
	while (x <= LIM){
		bit[x] += val;
		x += x & (-x);
	}
}

int get(int x){
	int res = 0;
	while (x > 0){
		res += bit[x];
		x -= x & (-x);
	}
	return res;
}

void upd(int pos, int d){
	if (pos > 1){
		int l = min(a[pos], a[pos-1])+1, r = max(a[pos], a[pos-1])-1;
		if (l <= r){
			update(l, d);
			update(r+1, -d);
		}
	}
	if (pos < N){
		int l = min(a[pos], a[pos+1])+1, r = max(a[pos], a[pos+1])-1;
		if (l <= r){
			update(l, d);
			update(r+1, -d);
		}
	}
}

int main(){
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	
	cin >> N >> M;
	for (int i = 1; i <= N; i++) cin >> a[i];
	
	for (int i = 1; i < N; i++){
		int l = min(a[i], a[i+1])+1, r = max(a[i], a[i+1])-1;
		if (l <= r){
			update(l, 1);
			update(r+1, -1);
		}
	}
	while (M--){
		int type; cin >> type;
		if (type == 1){
			int pos, val; cin >> pos >> val;
			upd(pos, -1);
			a[pos] = val;
			upd(pos, 1);
		}
		else{
			int H; cin >> H;
			cout << get(H) << '\n';
		}
	}
	return 0;
}

• Subtask 1: 22 / 22
• Subtask 2: 27 / 27
• Subtask 3: 51 / 51