Submission #850960

# Submission time Handle Problem Language Result Execution time Memory
850960 2023-09-18T03:48:31 Z iah Harbingers (CEOI09_harbingers) C++14
50 / 100
77 ms 22356 KB
#include<bits/stdc++.h>
using namespace std;

#define ll long long
#define ii pair < int , int >
#define fi first
#define se second
constexpr int Nmax = 1e5 + 5;
ll f[Nmax], v[Nmax], d[Nmax], s[Nmax];
vector < ii > adj[Nmax];
struct line {
	ll a, b;
	ll calc(ll x) {
		return a * x + b;
	}
	double intersect(line x) {
		return (double)(x.b - b) / (double)(a - x.a);
	}
}a[Nmax + 5];

struct ope {
	int id, old_top;
	line old_id;
};
stack < ope > st;
int top = 0;

void add(line x) {
	if (top <= 1 || (top >= 2 && a[top - 1].intersect(a[top]) < a[top - 1].intersect(x))) {
		st.push({top + 1, top, line{0, 0}});
		top++;
		a[top] = x;
		return;
	}
	
	int l = 1, r = top - 1, ans = 0;
	while (l <= r) {
		int mid = (l + r) / 2;
		if (a[mid].intersect(x) <= a[mid].intersect(a[mid + 1])) {
			ans = mid + 1;
			r = mid - 1;
		}
		else l = mid + 1;
	}
	
	st.push({ans, top, a[ans]});
	top = ans;
	a[ans] = x;
}

void undo() {
	auto t = st.top();
	st.pop();
	top = t.old_top;
	a[t.id] = t.old_id;
}

ll query(ll x) {
	if (top == 1) {
		return a[top].calc(x);
	}
	
	if (a[1].intersect(a[2]) > x) {
		return a[1].calc(x);
	}
	
	int l = 1, r = top - 1, ans = 0;
	while (l <= r) {
		int mid = (l + r) / 2;
		if (a[mid].intersect(a[mid + 1]) <= x) {
			ans = mid + 1;
			l = mid + 1;
		}
		else r = mid - 1;
	}
	return a[ans].calc(x);
}

void dfs(int i, int j) {
	if (i != 1) {
		f[i] = query(v[i]) + s[i] + v[i] * d[i];
	}
	add(line{-d[i], f[i]});
	for (auto x:adj[i]) {
		int u = x.fi, w= x.se;
		if (u == j) continue;
		d[u] = d[i] + w;
		dfs(u, i);
	}
	undo();
}
signed main() {
    if (fopen(".inp","r")) {
        freopen(".inp","r",stdin);
        freopen(".out","w",stdout);
    }
    cin.tie(0)->sync_with_stdio(0);
    int n;
    cin >> n;
    for (int i = 1; i < n; i++) {
    	int u, v, w;
    	cin >> u >> v >> w;
    	adj[u].push_back({v, w});
    	adj[v].push_back({u, w});
    } 
    for (int i = 2; i <= n; i++) {
    	cin >> s[i] >> v[i];
    }
    dfs(1, 0);
    for (int i = 2; i <= n; i++) {
    	cout << f[i] << " ";
    }
    return 0;
}

Compilation message

harbingers.cpp: In function 'int main()':
harbingers.cpp:94:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   94 |         freopen(".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~
harbingers.cpp:95:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   95 |         freopen(".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 6488 KB Output isn't correct
2 Correct 3 ms 7000 KB Output is correct
3 Correct 27 ms 13804 KB Output is correct
4 Correct 44 ms 16860 KB Output is correct
5 Correct 48 ms 19536 KB Output is correct
6 Correct 69 ms 22356 KB Output is correct
7 Incorrect 36 ms 14080 KB Output isn't correct
8 Incorrect 77 ms 17872 KB Output isn't correct
9 Incorrect 60 ms 19796 KB Output isn't correct
10 Incorrect 58 ms 18544 KB Output isn't correct