Submission #409662

#	Time	Username	Problem	Language	Result	Execution time	Memory
409662		anime	Fireworks (APIO16_fireworks)	C++14	7 / 100	5 ms	4980 KiB

fireworks

#include <bits/stdc++.h>
using namespace std;
#define int long long
#define pii pair<int,int>
#define OK puts("OK");
#define NO puts("NO");
#define YES puts("YES");
#define fr first
#define sc second
#define ret return
#define scanl(a) scanf("%lld",&a);
#define scanll(a,b) scanf("%lld %lld",&a, &b);
#define scanlll(a,b,c) scanf("%lld %lld %lld",&a,&b,&c);
#define scan1(a) scanf("%lld",&a);
#define scan2(a,b) scanf("%d %lld",&a, &b);
#define scan3(a,b,c) scanf("%d %d %d",&a,&b,&c);
#define all(s) s.begin(),s.end()
#define allr(s) s.rbegin(),s.rend()
#define pb push_back
#define sz(v) (int)v.size()
#define umax(a,b) a = max(a,b);
#define umin(a,b) a = min(a,b);
#define endi puts("");
#define eps 1e-12
const int N = 1e5+12,INF=1e18+7;
vector <int> der[N],v;
vector <pii> g[N];
void dfs_build(int x,int sum){

    if (g[x].empty()){
        der[x].pb(sum);
        v.pb(sum);
        ret ;
    }

    for (pii to:g[x]){
        dfs_build(to.fr,sum+to.sc);
        der[x].insert(der[x].end(),all(der[to.fr]));
    }
    sort(all(der[x]));
}

int get_ans(int x,int sum,int ch){
    int r = der[x][der[x].size()/2],ans = 0;
    int l = der[x][(der[x].size()-1)/2];
    if (l+ch <= sum && sum <= r+ch){}
    else if (r+ch < sum){
        int z = sum-r-ch;
        ans += z;
        ch += z;
    }
    else if (l+ch > sum){
        int z = l+ch-sum;
        ans += z;
        ch -= z;
    }

    for (pii to:g[x]){
        ans += get_ans(to.fr,sum,ch);
    }


    ret ans;
}


main(){
    int n,m,i,j,sum=0,ans=INF;
    cin>>n>>m;
    for (i=2;i<=m+n;++i){
        int x,y;
        cin>>x>>y;
        g[x].pb({i,y});

    }
    dfs_build(1,0);
    sort(all(v));
    for (int x:v){
        ans = min(ans,get_ans(1,x,0));
    }

    cout <<ans;


}







/*
8 7
1 5
2 3
2 8
3 2
3 3
4 6
4 5
5 6
5 3
6 8
7 5
7 1
8 3
8 6
*/

Compilation message (stderr)

fireworks.cpp:67:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   67 | main(){
      | ^~~~
fireworks.cpp: In function 'int main()':
fireworks.cpp:68:15: warning: unused variable 'j' [-Wunused-variable]
   68 |     int n,m,i,j,sum=0,ans=INF;
      |               ^
fireworks.cpp:68:17: warning: unused variable 'sum' [-Wunused-variable]
   68 |     int n,m,i,j,sum=0,ans=INF;
      |                 ^~~

• Subtask 1: 7 / 7
• Subtask 2: 0 / 19
• Subtask 3: 0 / 29
• Subtask 4: 0 / 45