#include<bits/stdc++.h>
#define rall(x) x.rbegin(), x.rend()
#define fi first
#define se second
#define ve vector
typedef long long ll;
using namespace std;
const int N = 350000;
priority_queue<ll> ql[N];
priority_queue<ll, vector<ll>, greater<ll>> qr[N];
unsigned ll ans=0;
vector<pair<int, ll>> g[N];
void add(ll val, int& i, int x){
if(ql[i].top()<val && val < qr[i].top()){
if(x<0){
ql[i].push(val);
}
else{
qr[i].push(val);
}
}
else if(ql[i].top()>=val){
if(x>0){
ans += ql[i].top()-val;
qr[i].push(ql[i].top());
ql[i].pop();
}
ql[i].push(val);
}
else if(qr[i].top()<=val){
if(x<0){
ans += val-qr[i].top();
ql[i].push(qr[i].top());
qr[i].pop();
}
qr[i].push(val);
}
}
void unite(int v, int u){
bool sw = 0;
if(ql[u].size()+qr[u].size() > ql[v].size()+qr[v].size()){swap(v, u); sw=1;}
while(!ql[u].empty()){
add(ql[u].top(), v, -1);
ql[u].pop();
}
while(!qr[u].empty()){
add(qr[u].top(), v, 1);
qr[u].pop();
}
if(sw){
ql[v].swap(ql[u]);
qr[v].swap(qr[u]);
}
}
void dfs(int v){
for(int i = 0;i<g[v].size();i++){
int son = g[v][i].first;
ll w = g[v][i].second;
dfs(son);
if(!g[son].size()){
ql[son].push(w);
qr[son].push(w);
}
else{
int l = ql[son].top(), r = qr[son].top();
ql[son].pop();
ql[son].push(l+w);
while(!qr[son].empty())qr[son].pop();
qr[son].push(r+w);
}
unite(v, son);
}
}
int main(){
ios_base::sync_with_stdio(0);cin.tie(0);
int n, m;
cin>>n>>m;
for(int i = 1; i<n+m;i++){
int an;ll c;
cin>>an>>c;an--;
g[an].push_back({i, c});
}
dfs(0);
cout<<ans<<'\n';
return 0;
}
Compilation message
fireworks.cpp:12:13: error: expected initializer before 'ans'
12 | unsigned ll ans=0;
| ^~~
fireworks.cpp: In function 'void add(ll, int&, int)':
fireworks.cpp:26:13: error: 'ans' was not declared in this scope; did you mean 'abs'?
26 | ans += ql[i].top()-val;
| ^~~
| abs
fireworks.cpp:34:13: error: 'ans' was not declared in this scope; did you mean 'abs'?
34 | ans += val-qr[i].top();
| ^~~
| abs
fireworks.cpp: In function 'void dfs(int)':
fireworks.cpp:61:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
61 | for(int i = 0;i<g[v].size();i++){
| ~^~~~~~~~~~~~
fireworks.cpp: In function 'int main()':
fireworks.cpp:90:11: error: 'ans' was not declared in this scope; did you mean 'abs'?
90 | cout<<ans<<'\n';
| ^~~
| abs
