Submission #1021405

#	Time	Username	Problem	Language	Result	Execution time	Memory
1021405		Nika533	Designated Cities (JOI19_designated_cities)	C++14	100 / 100	554 ms	60756 KiB

designated_cities

#pragma gcc diagnostic "-std=c++1z"
#include <bits/stdc++.h>
#define int long long
#define pb push_back
#define f first
#define s second
#define MOD 1000000007
#define pii pair<int,int>
#define all(x) (x).begin(),(x).end()
#define allr(x) (x).rbegin(),(x).rend()
using namespace std;

const int N=2e5+5;
int n,m,T,k,q,tot,sum,val[N],ans[N];
pii mx={0,0};
vector<pair<int,pii>> g[N];

pii ml[N];
int parent[N];

void dfs_build(int x, int p) {
     ml[x]={0,x}; parent[x]=p;
     for (auto A:g[x]) {
          int y=A.f,w1=A.s.f,w2=A.s.s;
          if (y==p) continue;
          dfs_build(y,x); ml[x]=max(ml[x],{ml[y].f+w1,ml[y].s});
     }
}

void solve(int root) {
     // cout<<"ROOT "<<root<<endl;
     dfs_build(root,0);
     vector<bool> used(n+1,0); used[0]=1;
     priority_queue<pii> q; q.push(ml[root]);
     int cur_ans=tot-val[root],cur_ind=2;
     while (!q.empty()) {
          pii AA=q.top(); q.pop();
          int v=AA.s,num=AA.f;
          cur_ans-=num;
          while (!used[v]) {
               used[v]=1;
               for (auto A:g[v]) {
                    int u=A.f,w1=A.s.f,w2=A.s.s; 
                    if (u!=parent[v] && !used[u]) q.push({ml[u].f+w1,ml[u].s});
               }
               v=parent[v];
          }
          ans[cur_ind]=min(ans[cur_ind],cur_ans); cur_ind++;
     }
     for (int i=cur_ind; i<=n; i++) ans[i]=0;
}

void dfs0(int x, int p) {
     for (auto A:g[x]) {
          int y=A.f,w1=A.s.f,w2=A.s.s;
          if (y==p) continue;
          sum+=w2; dfs0(y,x);
     }
}
void dfs1(int x, int p) {
     val[x]=sum; 
     for (auto A:g[x]) {
          int y=A.f,w1=A.s.f,w2=A.s.s;
          if (y==p) continue;
          sum+=w1-w2; dfs1(y,x); sum-=w1-w2; 
     }
}
void dfs(int x, int p, int dist) {
     mx=max(mx,{dist+val[x],x});
     for (auto A:g[x]) {
          int y=A.f,w1=A.s.f,w2=A.s.s;
          if (y==p) continue;
          dfs(y,x,dist+w1+w2);
     }
}

void test_case() {
     cin>>n;
     for (int i=1; i<=n-1; i++) {
          int a,b,c,d; cin>>a>>b>>c>>d;
          g[a].pb({b,{c,d}}); g[b].pb({a,{d,c}});
          tot+=c+d;
     }
     cin>>q;
     int query[q+1];
     for (int i=1; i<=q; i++) cin>>query[i];

     dfs0(1,0); dfs1(1,1);
     dfs(1,0,val[1]); int r1=mx.s; dfs(r1,0,val[r1]); int r2=mx.s;

     ans[1]=1e18;
     for (int i=1; i<=n; i++) ans[1]=min(ans[1],tot-val[i]);
     for (int i=2; i<=n; i++) ans[i]=1e18;

     solve(r1); solve(r2);

     for (int i=1; i<=q; i++) cout<<ans[query[i]]<<endl;
}
main () {
	ios :: sync_with_stdio(0);
	cin.tie(0); cout.tie(0);
	T=1; 
	while (T--) test_case();
}

Compilation message (stderr)

designated_cities.cpp:1: warning: ignoring '#pragma gcc diagnostic' [-Wunknown-pragmas]
    1 | #pragma gcc diagnostic "-std=c++1z"
      | 
designated_cities.cpp: In function 'void dfs_build(long long int, long long int)':
designated_cities.cpp:24:30: warning: unused variable 'w2' [-Wunused-variable]
   24 |           int y=A.f,w1=A.s.f,w2=A.s.s;
      |                              ^~
designated_cities.cpp: In function 'void solve(long long int)':
designated_cities.cpp:43:40: warning: unused variable 'w2' [-Wunused-variable]
   43 |                     int u=A.f,w1=A.s.f,w2=A.s.s;
      |                                        ^~
designated_cities.cpp: In function 'void dfs0(long long int, long long int)':
designated_cities.cpp:55:21: warning: unused variable 'w1' [-Wunused-variable]
   55 |           int y=A.f,w1=A.s.f,w2=A.s.s;
      |                     ^~
designated_cities.cpp: At global scope:
designated_cities.cpp:99:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   99 | main () {
      | ^~~~

• Subtask 1: 6 / 6
• Subtask 2: 7 / 7
• Subtask 3: 9 / 9
• Subtask 4: 17 / 17
• Subtask 5: 17 / 17
• Subtask 6: 44 / 44