Submission #1258077

#	Time	Username	Problem	Language	Result	Execution time	Memory
1258077		nicecoder37	Fountain (eJOI20_fountain)	C++20	100 / 100	947 ms	38688 KiB

fountain

#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx,avx2,fma")
#include <bits/stdc++.h>
#define fast ios_base::sync_with_stdio(false),cin.tie(NULL),cout.tie(NULL)
#define fi first
#define se second
#define space " "
#define endl "\n"
#define gcd __gcd
#define mp make_pair
#define pb push_back
#define pf push_front
#define lb lower_bound
#define ub upper_bound
#define md 1000000007
#define inf 1000000000000000
#define li 100005
#define int long long
using namespace std;
int T,Q,n,m,d[li],c[li],subtree[li],lca[li][25],x,y;
string s,t;
vector<int> v[li];
set<pair<int,int> > st;
void dfs(int node,int ata){
	lca[node][0]=ata;
	//~ printf("Child Costs: %d %d %d %d\n",node,ata,subtree[node],subtree[ata]);
	subtree[node]+=subtree[ata];
	for(int i=0;i<(int)v[node].size();i++){
		int go=v[node][i];
		if(go==ata) continue;
		dfs(go,node);
	}
}
int32_t main(){
	scanf("%lld %lld",&n,&Q);
	for(int i=1;i<=n;i++){
		scanf("%lld %lld",&d[i],&c[i]);                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            //~ IYYEAH
		subtree[i]=c[i];
	}
	d[n+1]=inf;
	c[n+1]=0;
	st.insert(mp(d[n+1],n+1));
	for(int i=n;i>=1;i--){
		while((int)st.size()){
			pair<int,int> temp=*st.begin();
			if(temp.fi<=d[i])st.erase(st.begin());
			else break;
		}
		pair<int,int> temp=*st.begin();
		v[i].pb(temp.se);
		v[temp.se].pb(i);
		st.insert(mp(d[i],i));
		//~ printf("Edges: %d %d\n",i,temp.se);
	}
	dfs(n+1,0);
	for(int i=1;i<=20;i++){
		for(int j=1;j<=n+1;j++){
			lca[j][i]=lca[lca[j][i-1]][i-1];
		}
	}
	while(Q--){
		scanf("%lld %lld",&x,&y);
		//~ printf("xD %d\n",subtree[x]);
		//~ if(subtree[x]<y){printf("0\n"); continue;}
		int bas=1,son=5*n;
		while(bas<=son){
			int mid=(bas+son)/2;
			int sayi=mid,node=x;
			for(int i=20;i>=0;i--){
				if(sayi>=(1ll<<i)){sayi-=(1ll<<i); node=lca[node][i];}
			}
			if(subtree[x]-subtree[node]>=y) son=mid-1;
			else bas=mid+1;
		}
		//~ printf("Debuggi %d %d\n",bas,son);
		for(int i=20;i>=0;i--){
			if(son>=(1ll<<i)){son-=(1ll<<i); x=lca[x][i];}
		}
		if(x==0 || x==n+1) printf("0\n");
		else printf("%lld\n",x);
	}
	return 0;
}

Compilation message (stderr)

fountain.cpp: In function 'int32_t main()':
fountain.cpp:35:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   35 |         scanf("%lld %lld",&n,&Q);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~
fountain.cpp:37:22: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   37 |                 scanf("%lld %lld",&d[i],&c[i]);                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            //~ IYYEAH
      |                 ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
fountain.cpp:62:22: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   62 |                 scanf("%lld %lld",&x,&y);
      |                 ~~~~~^~~~~~~~~~~~~~~~~~~

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