#include <iostream>
#include <bits/stdc++.h>
#define vi vector<int>
#define pb push_back
#define F first
#define S second
#define ll long long
#define vll vector<ll>
using namespace std;
const int tam=1e5+5;
int T[4*tam];
vll v;
void init(int nodo,int b, int e){
int L=2*nodo+1,R=L+1,mid=(b+e)/2;
if(b==e){
T[nodo]=v[b];
return;
}
init(L,b,mid);init(R,mid+1,e);
T[nodo]=max(T[L],T[R]);
}
int query(int nodo, int b, int e, int izq, int der){
int L=2*nodo+1,R=L+1,mid=(b+e)/2;
if(b>=izq && e<=der){
return T[nodo];
}
if(der<=mid){
return query(L,b,mid,izq,der);
}
if(izq>=mid+1){
return query(R,mid+1,e,izq,der);
}
return max(query(L,b,mid,izq,der),query(R,mid+1,e,izq,der));
}
vi G[tam];
vll C;
int dp[tam][20];
int depth[tam];
ll peso[tam];
void init(int nodo,int p ,int d,int P){
peso[nodo]=P;
depth[nodo]=d;
dp[nodo][0]=p;
for(int i=0;i<G[nodo].size();i++){
int it=G[nodo][i];
if(it==p)continue;
init(it,nodo,d+1,P+C[it-1]);
}
}
void initbl(){
init(0,-1,0,1e9);
for(int i=1;i<=19;i++){
for(int l=0;l<tam;l++){
if(dp[l][i-1]==-1)continue;
dp[l][i]=dp[dp[l][i-1]][i-1];
}
}
}
pair<ll,ll> _find(int nodo, int num){//retorna la suma y el indice
int nodoin=nodo;
for(int i=19;i>=0;i--){
if(nodo==-1)return {0,0};
if(num&(1<<i)){
nodo=dp[nodo][i];
}
}
return {peso[nodoin]-peso[nodo]+C[nodo-1],nodo};
}
int main()
{
ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
ll n,q,d,c;
cin>>n>>q;
for(int i=0;i<n;i++){
cin>>d>>c;
v.pb(d);C.pb(c);
}
v.pb(5000);
init(0,0,n);
for(int i=0;i<n;i++){
int b=i+1,e=n;
int pos;
while(b<=e){
int mid=(b+e)/2;
ll Q=query(0,0,n,b,mid);
if(b==e){
pos=b;
break;
}
if(Q>v[i]){
pos=mid;
e=mid;
}else{
b=mid+1;
pos=e;
}
}
if(pos==n){
G[i+1].pb(0);G[0].pb(i+1);
}else{
G[i+1].pb(pos+1);G[pos+1].pb(i+1);
}
}
initbl();
ll R,V;
while(q--){
cin>>R>>V;
int b=0,e=depth[R];
int res=0;
while(b<=e){
int mid=(b+e)/2;
pair<ll,ll> Q=_find(R,mid);
if(b==e){
res=Q.S;
break;
}
if(Q.F>=V){
res=Q.S;
e=mid;
}else{
b=mid+1;
}
}
if(res>n)res=0;
cout<<res<<"\n";
}
return 0;
}
//freopen("input.2_03","r",stdin);
Compilation message
fountain.cpp: In function 'void init(int, int, int, int)':
fountain.cpp:44:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
44 | for(int i=0;i<G[nodo].size();i++){
| ~^~~~~~~~~~~~~~~
fountain.cpp: In function 'int main()':
fountain.cpp:99:11: warning: 'pos' may be used uninitialized in this function [-Wmaybe-uninitialized]
99 | if(pos==n){
| ^~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
16 ms |
10444 KB |
Output is correct |
2 |
Correct |
17 ms |
10556 KB |
Output is correct |
3 |
Correct |
17 ms |
10576 KB |
Output is correct |
4 |
Correct |
18 ms |
10580 KB |
Output is correct |
5 |
Correct |
18 ms |
10640 KB |
Output is correct |
6 |
Correct |
18 ms |
10600 KB |
Output is correct |
7 |
Correct |
17 ms |
10592 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
861 ms |
23716 KB |
Output is correct |
2 |
Correct |
823 ms |
22936 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
16 ms |
10444 KB |
Output is correct |
2 |
Correct |
17 ms |
10556 KB |
Output is correct |
3 |
Correct |
17 ms |
10576 KB |
Output is correct |
4 |
Correct |
18 ms |
10580 KB |
Output is correct |
5 |
Correct |
18 ms |
10640 KB |
Output is correct |
6 |
Correct |
18 ms |
10600 KB |
Output is correct |
7 |
Correct |
17 ms |
10592 KB |
Output is correct |
8 |
Correct |
861 ms |
23716 KB |
Output is correct |
9 |
Correct |
823 ms |
22936 KB |
Output is correct |
10 |
Correct |
18 ms |
10584 KB |
Output is correct |
11 |
Correct |
334 ms |
15460 KB |
Output is correct |
12 |
Correct |
1254 ms |
25108 KB |
Output is correct |
13 |
Correct |
753 ms |
23412 KB |
Output is correct |
14 |
Correct |
462 ms |
21552 KB |
Output is correct |
15 |
Correct |
383 ms |
22324 KB |
Output is correct |