Submission #587031

#	Time	Username	Problem	Language	Result	Execution time	Memory
587031		8e7	Fish 2 (JOI22_fish2)	C++17	25 / 100	4075 ms	4888 KiB

fish2

//Challenge: Accepted
#include <bits/stdc++.h>
using namespace std;
#ifdef zisk
void debug(){cout << endl;}
template<class T, class ... U> void debug(T a, U ... b){cout << a << " ", debug(b...);}
template<class T> void pary(T l, T r) {
	while (l != r) cout << *l << " ", l++;
	cout << endl;
}
#else
#define debug(...) 0
#define pary(...) 0
#endif
#define ll long long
#define maxn 100005
#define pii pair<int, int>
#define ff first
#define ss second
#define io ios_base::sync_with_stdio(0);cin.tie(0);
int a[maxn], b[maxn], lef[maxn], rig[maxn];
int lc[maxn], rc[maxn], cnt[maxn];
ll pref[maxn];
void dfs(int n, int par) {
	if (lc[n] != -1) dfs(lc[n], n);
	if (rc[n] != -1) dfs(rc[n], n);
	ll sum = pref[rig[n]] - (lef[n] ? pref[lef[n]-1] : 0);	
	if (sum >= b[par]) cnt[n] = 1 + cnt[lc[n]] + cnt[rc[n]];	
	else cnt[n] = 0;
}
int main() {
	io
	int n, q;
	cin >> n;	
	for (int i = 1;i <= n;i++) cin >> a[i];
	cin >> q;
	while (q--) {
		int type;
		cin >> type;
		if (type == 1) {
			int x, y;
			cin >> x >> y;
			a[x] = y;
		} else {
			int l, r;
			cin >> l >> r;
			int s = r - l + 1;
			for (int i = l;i <= r;i++) b[i-l] = a[i];
			for (int i = 0;i < s;i++) {
				pref[i] = b[i] + (i ? pref[i-1] : 0);
				cnt[i] = 0;
				rig[i] = s-1;
				lef[i] = 0;
				lc[i] = rc[i] = -1;
			}
			stack<int> stk;
			for (int i = 0;i < s;i++) {
				while (stk.size() && b[i] >= b[stk.top()]) {
					lc[i] = stk.top();
					rig[stk.top()] = i-1;
					stk.pop();
				}
				if (stk.size()) {
					rc[stk.top()] = i;
					lef[i] = stk.top()+1;
				}
				stk.push(i);
			}
			while (stk.size() > 1) stk.pop();
			int root = stk.top();
			dfs(root, root);	
			cout << cnt[root] << "\n";
		}
	}
}

• Subtask 1: 5 / 5
• Subtask 2: 8 / 8
• Subtask 3: 12 / 12
• Subtask 4: 0 / 23
• Subtask 5: 0 / 35
• Subtask 6: 0 / 17