Submission #704598

#	Time	Username	Problem	Language	Result	Execution time	Memory
704598		thrasherr_1	Fountain (eJOI20_fountain)	C++17	0 / 100	85 ms	31824 KiB

fountain

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

#define ff first
#define ss second
#define ll long long
#define pb push_back
#define lb lower_bound
#define ub upper_bound
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define ones(x) __builtin_popcount(x)
#define remove(v)  v.erase(unique(all(v)), v.end())
#define rep(i, a, b) for(int i = a; i <= b; i++)
#define per(i, a, b) for(int i = a; i >= b; i--)

#ifdef local
#include "C:\debug.h"
#else
#define dbg(x...) 42
#endif

#define int ll

const int N = 1e5 + 2 ;

int n , q , d[N] , c[N] , up[N][19] , sum[N][19] ;

void dfs(int v , int p) {
    rep(i , 2 , 17) {
        up[v][i] = up[up[v][i - 1]][i - 1] ;
    }
}

void solve(){
    cin >> n >> q ;
    rep(i , 1 , n) {
        cin >> d[i] >> c[i] ;
    }
    stack<pair<int,int>> s ;
    s.push({INT_MAX , n + 1}) ;
    per(i , n , 1){
        up[i][0] = i , sum[i][0] = c[i] ;
        while(sz(s) && s.top().first < d[i]) s.pop() ;
        if(sz(s)) up[i][1] = s.top().second , sum[i][1] = c[i] + c[s.top().second] ;
        else up[i][1] = i ;
        s.push({d[i] , i}) ;
    }
    per(i , n , 1) {
        rep(j , 2 , 18) {
            up[i][j] = up[up[i][j - 1]][j - 1]  ;
            up[i][j] = max(up[i][j] , up[i][j - 1]) ;
            if(up[i][j]) sum[i][j] = sum[i][j - 1] + c[up[i][j]] ;
        }
    }
    // rep(i , 1 , n) {
        // rep(j , 0 , 18) {
            // cout << sum[i][j] << ' '; 
        // }
        // cout << "\n" ;
    // }
    rep(i , 1 , q) {
        int ind  , k ; cin >> ind >> k ;
        per(j , 18 , 0) {
            if(k >= sum[ind][j]) {
                k -= sum[ind][j] ;
                if(up[ind][j]) ind = up[ind][j] ;
                k += c[ind] ;
            }
        }
        if(ind > n) {
            cout << 0 << "\n" ;
        }else{
            rep(j , 0 , 18) {
                if(sum[ind][j] >= k) {
                    ind = up[ind][j] ;
                    break ;
                }
            }
            cout << ind << "\n" ;
        }
        dbg(ind , k) ;
    }
    
}

signed main () {
	ios::sync_with_stdio(false) ;
	cin.tie(0) ;
	int test = 1 ;
	// cin >> test ; 
	for(int i = 1 ; i <= test ; i++) {
		solve() ;
	}
}

Compilation message (stderr)

fountain.cpp: In function 'void solve()':
fountain.cpp:20:19: warning: statement has no effect [-Wunused-value]
   20 | #define dbg(x...) 42
      |                   ^~
fountain.cpp:82:9: note: in expansion of macro 'dbg'
   82 |         dbg(ind , k) ;
      |         ^~~

• Subtask 1: 0 / 30
• Subtask 2: 0 / 30
• Subtask 3: 0 / 40