Submission #340092

#	Time	Username	Problem	Language	Result	Execution time	Memory
340092		Hazem	Putovanje (COCI20_putovanje)	C++14	110 / 110	288 ms	44140 KiB

putovanje

/*
ID: tmhazem1
LANG: C++14
TASK: pprime
*/

#include <bits/stdc++.h>
using namespace std;

#define S second
#define F first
#define LL long long

const int N = 2e5 + 10;


LL LINF = 100000000000000000;
LL INF = 1000000000;

LL par[N][30],pr[N],depth[N];
vector<pair<int,pair<LL,LL>>>adj[N];

void dfs(int i,int pre){

    par[i][0] = pre;
    for(int j=1;j<=20;j++)
        par[i][j] = par[par[i][j-1]][j-1];

    for(auto x:adj[i])
        if(x.F==pre)continue;
        else 
        depth[x.F] = depth[i]+1,dfs(x.F,i),pr[i] += pr[x.F];
}

int lca(int u,int v){

    if(depth[u]<depth[v])swap(u,v);

    for(int i=20;i>=0;i--)
        if(depth[u]-(1<<i)>=depth[v])
        u = par[u][i];

    if(u==v)return u;

    for(int i=20;i>=0;i--)
        if(par[u][i]!=par[v][i])
        u = par[u][i],v = par[v][i];
    
    return par[u][0];
}

LL dfs2(int i,int pre){

    LL ret = 0;
    for(auto x:adj[i])
        if(x.F==pre)continue;
        else ret += min(x.S.F*pr[x.F],x.S.S)+dfs2(x.F,i);
    
    return ret;
}

int main()
{
    //freopen("out.txt","w",stdout);
    int n;
    scanf("%d",&n);

    for(int i=1;i<n;i++){
        int u,v,c,c1;
        scanf("%d%d%d%d",&u,&v,&c,&c1);
        adj[u].push_back({v,{c,c1}});
        adj[v].push_back({u,{c,c1}});
    }

    dfs(1,1);
    for(int i=1;i<n;i++){
        int l = lca(i,i+1);
        pr[l] -= 2;
        pr[i]++;pr[i+1]++;
    }
    dfs(1,1);
    printf("%lld\n",dfs2(1,1));
}       

Compilation message (stderr)

putovanje.cpp: In function 'int main()':
putovanje.cpp:66:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   66 |     scanf("%d",&n);
      |     ~~~~~^~~~~~~~~
putovanje.cpp:70:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   70 |         scanf("%d%d%d%d",&u,&v,&c,&c1);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 20 / 20
• Subtask 2: 25 / 25
• Subtask 3: 65 / 65