oj.uz

Submission #813538

# Submission time Handle Problem Language Result Execution time Memory
813538 2023-08-07T19:53:47 Z Acanikolic Fountain (eJOI20_fountain) C++14
60 / 100
 1500 ms 32264 KB 
#include <bits/stdc++.h>
		 				 
#define pb push_back 
		
#define F first
		 
#define S second
		 
using namespace std;
		 
const int N = 1e5+10;
		 
const int mod = 1e9+7;
		 
const int inf = 1e18;	

const int lg = 18;

vector<int>g[N];
int up[N][lg],vis[N];
long long sm[N][lg];
pair<int,int>a[N];

void dfs(int x,int par) {
	vis[x] = 1;
	for(auto X:g[x]) {
		if(X != par) {
			dfs(X,x);
		}
	}
}
				
signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
	
	int n,Q;
	cin >> n >> Q;
	for(int i=1;i<=n;i++) cin >> a[i].F >> a[i].S;
	stack<pair<int,int>>st;
	for(int i=1;i<=n;i++) up[i][0] = i;
	for(int i=n;i>=1;i--) {
		while(st.size() && st.top().F <= a[i].F) st.pop();
		if(!st.empty()) {
			g[i].pb(st.top().S);
			up[i][0] = st.top().S;
			sm[i][0] = a[st.top().S].S;
			// /cout << i << " -> " << st.top().S << ' ' << a[st.top().S].S << endl;
			//g[st.top().S].pb(i);
		}
		st.push({a[i].F,i});
	}
	for(int i=1;i<=n;i++) if(!vis[i]) dfs(i,0);
	for(int j=1;j<lg;j++) {
		for(int i=1;i<=n;i++) {
			up[i][j] = up[up[i][j-1]][j-1];
			sm[i][j] = sm[i][j-1]+sm[up[i][j-1]][j-1];
		}
	}
	/*for(int i=1;i<=n;i++) {
		for(int j=0;j<lg;j++) cout << sm[i][j] << ' ';
		cout << endl;
	}*/
	while(Q--) {
		int index,val;
		cin >> index >> val;
		val -= a[index].S;
		for(int j=lg-1;j>=0;j--) {
			if(sm[index][j] <= val) {
				//cout << index << ' ' << j << ' ' << val << ' ' << sm[index][j] << endl;
				val -= sm[index][j];
				index = up[index][j];
			}
		}
		if(val > sm[index][0]) {
			cout << "0\n";
			continue;
		}
		if(val > 0) index = up[index][0];
		cout << index << '\n';
	}
    return 0; 
}

Compilation message

fountain.cpp:15:17: warning: overflow in conversion from 'double' to 'int' changes value from '1.0e+18' to '2147483647' [-Woverflow]
   15 | const int inf = 1e18;
      |                 ^~~~

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2644 KB Output is correct
2 Correct 2 ms 2772 KB Output is correct
3 Correct 2 ms 2772 KB Output is correct
4 Correct 2 ms 2900 KB Output is correct
5 Correct 2 ms 2900 KB Output is correct
6 Correct 2 ms 2900 KB Output is correct
7 Correct 2 ms 2900 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 155 ms 30516 KB Output is correct
2 Correct 146 ms 28424 KB Output is correct

Subtask #3
0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2644 KB Output is correct
2 Correct 2 ms 2772 KB Output is correct
3 Correct 2 ms 2772 KB Output is correct
4 Correct 2 ms 2900 KB Output is correct
5 Correct 2 ms 2900 KB Output is correct
6 Correct 2 ms 2900 KB Output is correct
7 Correct 2 ms 2900 KB Output is correct
8 Correct 155 ms 30516 KB Output is correct
9 Correct 146 ms 28424 KB Output is correct
10 Correct 2 ms 2900 KB Output is correct
11 Correct 900 ms 17500 KB Output is correct
12 Correct 228 ms 32264 KB Output is correct
13 Execution timed out 1591 ms 28568 KB Time limit exceeded
14 Halted 0 ms 0 KB -