Peli

input/code.cpp: In function 'int main()':
input/code.cpp:87:47: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   87 |                         if (reitit[i2].size() > i)
      |                             ~~~~~~~~~~~~~~~~~~^~~

#include <bits/stdc++.h>
#include <iostream>
#include <vector>

using namespace std;

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    int n, m, kyselyja, x, a, b;
    cin >> n >> m >> kyselyja;

    vector<int> v[n];

    for (int i = 0; i < m; i++)
    {
        cin >> a >> b;
        a--;
        b--;
        v[a].push_back(b);
        v[b].push_back(a);
    }

    // käydään jokainen kysely läpi
    for (int i = 0; i < kyselyja; i++)
    {
        cin >> a >> b >> x;
        a--;
        b--;

        if (x == 0)
        {
            if (a == b)
            {
                cout << "YES\n";
            }
            else
            {
                cout << "NO\n";
            }
            continue;
        }
        // etsitään lyhyimmän reitin pituus

        priority_queue<pair<int, int>> q;
        int kayty[n];
        int arvot[n];
        fill(kayty, kayty + n, 0);
        kayty[a] = 1;
        arvot[a] = 0;

        vector<int> reitit[n];
        int tulo[n];
        fill(tulo, tulo + n, -1);

        for (int vierus : v[a])
        {
            q.push(make_pair(-1, vierus));
            tulo[vierus] = a;
        }

        int lyhyin = a == b ? 0 : -1;
        int pienin_lisays = INT_MAX;

        while (!q.empty())
        {
            auto t = q.top();
            q.pop();

            if (-t.first > x)
            {
                break;
            }

            if (kayty[t.second])
            {
                int d = -t.first + arvot[t.second];
                if (d & 1)
                {
                    int raja = min(-t.first - 1, arvot[t.second]);

                    for (int i = 0; i < raja; i++)
                    {
                        int i2 = tulo[t.second];
                        if (reitit[i2].size() > i)
                        {
                            i2 = reitit[i2].at(i);
                        }

                        if (reitit[t.second].at(i) == i2)
                        {
                            d -= 2;
                        }
                    }

                    if (d < pienin_lisays)
                    {
                        pienin_lisays = d;
                    }
                }

                continue;
            }
            else
            {
                for (int val : reitit[tulo[t.second]])
                {
                    reitit[t.second].push_back(val);
                }
                reitit[t.second].push_back(tulo[t.second]);
            }

            if (t.second == b && lyhyin == -1)
            {
                lyhyin = -t.first;
            }

            kayty[t.second] = 1;
            arvot[t.second] = -t.first;
            for (int vierus : v[t.second])
            {
                q.push(make_pair(t.first - 1, vierus));
                if (tulo[vierus] == -1)
                {
                    tulo[vierus] = t.second;
                }
            }
        }

        if (lyhyin == -1)
        {
            cout << "NO\n";
            continue;
        }

        if (lyhyin > x)
        {
            cout << "NO\n";
            continue;
        }

        if (((x - lyhyin) & 1) == 0)
        {
            cout << "YES\n";
            continue;
        }

        if ((x - lyhyin) >= pienin_lisays)
        {
            cout << "YES\n";
            continue;
        }

        cout << "NO\n";
    }
}

/*
5 5 2
1 2
2 3
3 5
1 4
4 5


*/

Test 1

Group: 1, 2

Verdict: ACCEPTED

Test 2

Group: 1, 2

Verdict: ACCEPTED

Test 3

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 4

Group: 1, 2

Verdict: ACCEPTED

Test 5

Group: 1, 2

Verdict: WRONG ANSWER

Test 6

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 7

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 8

Group: 1, 2

Verdict: ACCEPTED

Test 9

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 10

Group: 2

Verdict: TIME LIMIT EXCEEDED