Submission #730177

#	Time	Username	Problem	Language	Result	Execution time	Memory
730177		lucri	Traffic (IOI10_traffic)	C++17	Compilation error	0 ms	0 KiB

traffic

//#include "traffic.h"
#include <bits/stdc++.h>
#include <stdio.h>

static int N,P[1000000],S[1000000],D[1000000];

std::vector<std::vector<int>>a;
int v[1000010],nr[1000010];
void parcurge(int nod,int ant)
{
    for(auto x:a[nod])
    {
        if(x!=ant)
        {
            parcurge(x,nod);
            v[nod]+=v[x];
        }
    }
    v[nod]+=nr[nod];
}
int LocateCentre(int N, int pp[], int S[], int D[]) {
    int n=N,ans,vans=2000000000,sf,fmax,vmax,rad;
    a.resize(n+5);
    for(int i=0;i<n-1;++i)
    {
        nr[i]=pp[i];
        a[S[i]].push_back(D[i]);
        a[D[i]].push_back(S[i]);
    }
    nr[n-1]=pp[n-1];
    parcurge(n/2,-1);
    ans=n/2;
    rad=n/2;
    do
    {
        sf=0;
        vmax=0;
        for(auto x:a[rad])
        {
            sf+=v[x];
            if(v[x]>vmax)
            {
                vmax=v[x];
                fmax=x;
            }
        }
        if(vmax<vans)
        {
            vans=vmax;
            ans=rad;
        }
        v[fmax]=v[rad];
        v[rad]=sf-vmax+nr[rad];
        rad=fmax;
    }while(fmax!=ans);
    return ans;
}


int main(){
   int i;
   scanf("%d",&N);
   for (i=0;i<N;i++) scanf("%d",&P[i]);
   for (i=0;i<N-1;i++) scanf("%d%d",&S[i],&D[i]);
   int r = LocateCentre(N,P,S,D);
   printf("%d\n",r);
   return 0;
}

Compilation message (stderr)

traffic.cpp: In function 'int main()':
traffic.cpp:62:9: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   62 |    scanf("%d",&N);
      |    ~~~~~^~~~~~~~~
traffic.cpp:63:27: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   63 |    for (i=0;i<N;i++) scanf("%d",&P[i]);
      |                      ~~~~~^~~~~~~~~~~~
traffic.cpp:64:29: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   64 |    for (i=0;i<N-1;i++) scanf("%d%d",&S[i],&D[i]);
      |                        ~~~~~^~~~~~~~~~~~~~~~~~~~
traffic.cpp: In function 'int LocateCentre(int, int*, int*, int*)':
traffic.cpp:55:16: warning: 'fmax' may be used uninitialized in this function [-Wmaybe-uninitialized]
   55 |     }while(fmax!=ans);
      |            ~~~~^~~~~
/usr/bin/ld: /tmp/ccewCAxp.o: in function `main':
grader.cpp:(.text.startup+0x0): multiple definition of `main'; /tmp/cc6gp9Nm.o:traffic.cpp:(.text.startup+0x0): first defined here
collect2: error: ld returned 1 exit status