Submission #1128448

#	Time	Username	Problem	Language	Result	Execution time	Memory
1128448		cbnhtmanh	Election Campaign (JOI15_election_campaign)	C++20	10 / 100	56 ms	11848 KiB

election_campaign

#include <bits/stdc++.h>
#define fi(i, a, b) for( int i = a; i <= b; i++ )
#define fid(i, a, b) for( int i = a; i >= b; i-- )
#define getbit(x, i) ((x>>i)&1)
#define ll long long
#define pb push_back
#define pii pair<int,int>
#define pli pair<ll,int>
#define pll pair<ll,ll>
#define st first
#define nd second
#define mp make_pair
#define HTManh ""
#define maxn 100009
#define endl '\n'
using namespace std;

int n;
vector<int> a[100009];
int m;
struct dl
{
    int u, v;
    int c;
} tv[100009];

bool check()
{
    fi(u,1,n) for(int v: a[u]) if (u < v && u != v-1) return 0;
    return 1;
}

vector<pii> truyvan[100009];
ll mx[100009];

void sub23()
{
    //cout << "gay" << endl;
    fi(i,1,m)
    {
        int u = tv[i].u, v = tv[i].v, c = tv[i].c;
        if (u > v) swap(u, v);
        truyvan[v].pb({u, c});
    }
    fi(i,1,n)
    {
        ll gt = 0;
        for(pii tg: truyvan[i])
        {
            gt = max(gt, mx[tg.st - 1] + tg.nd);
        }
        mx[i] = max(mx[i-1], gt);
    }
    cout << mx[n] << endl;
}

void sub1()
{

}

void subac()
{

}

int main()
{
	ios_base::sync_with_stdio(0);
	cin.tie(NULL); cout.tie(NULL);
	if (fopen(HTManh".inp", "r"))
    {
        freopen(HTManh".inp", "r", stdin);
        freopen(HTManh".out", "w", stdout);
    }

    cin >> n;
    fi(i,1,n-1)
    {
        int x, y;
        cin >> x >> y;
        a[x].pb(y);
        a[y].pb(x);
    }
    cin >> m;
    fi(i,1,m) cin >> tv[i].u >> tv[i].v >> tv[i].c;

    if (check()) sub23();
    else
    {
        if (m <= 15) sub1();
        else subac();
    }
}

Compilation message (stderr)

election_campaign.cpp: In function 'int main()':
election_campaign.cpp:73:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   73 |         freopen(HTManh".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
election_campaign.cpp:74:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   74 |         freopen(HTManh".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 10
• Subtask 2: 5 / 5
• Subtask 3: 5 / 5
• Subtask 4: 0 / 30
• Subtask 5: 0 / 10
• Subtask 6: 0 / 40