Submission #977459

#	Time	Username	Problem	Language	Result	Execution time	Memory
977459		shoryu386	Money (IZhO17_money)	C++17	100 / 100	156 ms	21728 KiB

money

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

#define int long long

#define MX 1000007
int fwt[MX+1];
#define lsb(x) (x&(-x))

void update(int x, int k){
	x++;
	
	for (; x < MX; x += lsb(x)){
		fwt[x] += k;
	}
}

int sum(int x){
	x++;
	
	int res = 0;
	for (; x != 0; x -= lsb(x)){
		res += fwt[x];
	}
	
	return res;
}

int query(int a, int b){
	if (b < a) return 0;
	return sum(b) - sum(a-1);
}

main(){ ios_base::sync_with_stdio(0); cin.tie(0);
	
	int n; cin >> n;
	//attempt greedy
	
	int arr[n]; for (int x = 0; x < n; x++) cin >> arr[x];
	
	bitset<1000007> taken;
	int ans = 0;
	for (int zzz = 0; zzz < n; zzz++){
		if (taken[zzz]){
			continue;
		}
		
		ans++;
		
		taken[zzz] = 1;
		vector<int> items; items.push_back(arr[zzz]);
		
		for (int y = zzz+1; y < n; y++){
			if (items.back() <= arr[y] && query(arr[zzz]+1, arr[y]-1) == 0){
				taken[y] = 1;
				items.push_back(arr[y]);
			}
			else{
				break;
			}
		}
		
		for (auto y : items){
			update(y, 1);
		}
		
	}
	
	cout << ans;
	
	
}

Compilation message (stderr)

money.cpp:34:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   34 | main(){ ios_base::sync_with_stdio(0); cin.tie(0);
      | ^~~~

• Subtask 1: 9 / 9
• Subtask 2: 16 / 16
• Subtask 3: 20 / 20
• Subtask 4: 55 / 55