Submission #414856

#	Time	Username	Problem	Language	Result	Execution time	Memory
414856		JediMaster11	Traffic (IOI10_traffic)	C++17	Compilation error	0 ms	0 KiB

traffic

#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define uint unsigned int
#define ull unsigned long long
#define endl "\n"
#define elif else if
#define fo(i, a, b) for (int i = a; i < (int)b; i++)
#define rfo(i, a, b) for (int i = a - 1; i >= b; i--)
#define v(i) vector<i>
#define vll vector<long long>
#define vstr vector<string>
#define pairll pair<long long, long long>
#define vpairll vector<pair<long long, long long>>
#define print(x) cout << x << "\n"

#define pushall(x, n)                   \
    x.resize(n);                        \
    for (int zz = 0; zz < (int)n; zz++) \
    {                                   \
        cin >> x[zz];                   \
    }

vector<vector<ll>> roads;
vll fans;
ll smallestMax = LLONG_MAX;
ll smallPlace=0;

ll recur(ll on, ll prev, ll total)
{

    if(roads[on].size()==1 && prev!=-1)//at the end
    {

        return fans[on];
 
    }

    ll maxR=-1;
    ll sum=0;
    for(auto x : roads[on]){
        if(x != prev){
            ll tmp = recur(x, on, total+fans[on]);
            maxR = max(maxR, tmp);
            sum+=tmp;
        }
    }

if(max(maxR, total) < smallestMax){
    smallestMax = max(maxR, total);
    smallPlace=on;
}

    //should return the sum of all recurs I think, but the max should be used to find the smallestMax
    return sum+fans[on];


    //compare total to all the values of recur added together, looking for the smallest max


}

int main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);

    ll num;
    cin >> num;

    pushall(fans, num);

    roads.resize(num);

    fo(i, 0, num - 1)
    {
        ll n1, n2;

        cin >> n1 >> n2;

        roads[n1].push_back(n2);
        roads[n2].push_back(n1);
    }

    ll on = 0;
    while (roads[on].size() > 1)
    {
        on++;
    } //gets the start to a point with only 1 road

    if(num==1){
        print(0);
        return 0;
    }elif(num==2){
        print((fans[0] > fans[1] ? 1 : 0));
        return 0;
    }


    recur(on, -1, 0);

    print(smallPlace);

    //smallest max

    return 0;
}

// dont want it on a city with only 1 road, its better to chose cities with a bigger population, as that doesnt add to the congestion
// in geenral, the more roads the better (as congestion is split between multiple roads)

Compilation message (stderr)

/usr/bin/ld: /tmp/ccrWGPBf.o: in function `main':
grader.cpp:(.text.startup+0x0): multiple definition of `main'; /tmp/ccl0d9ih.o:traffic.cpp:(.text.startup+0x0): first defined here
/usr/bin/ld: /tmp/ccrWGPBf.o: in function `main':
grader.cpp:(.text.startup+0xe1): undefined reference to `LocateCentre(int, int*, int*, int*)'
collect2: error: ld returned 1 exit status