Submission #968709

#	Time	Username	Problem	Language	Result	Execution time	Memory
968709		raphaelp	Paths (BOI18_paths)	C++14	100 / 100	499 ms	41600 KiB

paths

#include <bits/stdc++.h>
using namespace std;
int main()
{
    long long N, M, K;
    cin >> N >> M >> K;
    vector<long long> C(N);
    for (long long i = 0; i < N; i++)
    {
        cin >> C[i];
        C[i]--;
    }
    vector<vector<long long>> AR(N);
    vector<vector<long long>> voisins(N, vector<long long>(K));
    for (long long i = 0; i < M; i++)
    {
        long long a, b;
        cin >> a >> b;
        a--, b--;
        AR[a].push_back(b);
        AR[b].push_back(a);
        voisins[a][C[b]]++;
        voisins[b][C[a]]++;
    }
    long long tot = 0, half = 0;
    for (long long i = 0; i < N; i++)
    {
        vector<long long> count((1 << K));
        for (long long j = 0; j < AR[i].size(); j++)
        {
            count[(1 << C[AR[i][j]])]++;
            for (long long k = 0; k < K; k++)
            {
                if (k == C[AR[i][j]])
                    continue;
                count[((1 << C[AR[i][j]]) | (1 << k))] += voisins[AR[i][j]][k];
            }
        }
        for (long long j = 1; j < (1 << K); j++)
        {
            if (j & (1 << C[i]))
                continue;
            if (__builtin_popcount(j) > 2)
                continue;
            if (__builtin_popcount(j) == 1 && K >= 2)
                half += count[j];
            if (__builtin_popcount(j) == 1 && K >= 3)
            {
                for (long long k = 0; k < K; k++)
                {
                    if ((j & (1 << k)) || k == C[i])
                        continue;
                    half += count[(1 << k)] * count[j];
                }
            }
            if (__builtin_popcount(j) == 2 && K >= 4)
            {
                for (long long k = 0; k < K; k++)
                {
                    if ((j & (1 << k)) || k == C[i])
                        continue;
                    half += count[(1 << k)] * count[j];
                }
            }
            if (__builtin_popcount(j) == 2 && K >= 5)
            {
                half += count[j] * count[((1 << K) - 1 - j - (1 << C[i]))];
            }
        }
    }
    cout << tot * 2 + half;
}

Compilation message (stderr)

paths.cpp: In function 'int main()':
paths.cpp:29:33: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   29 |         for (long long j = 0; j < AR[i].size(); j++)
      |                               ~~^~~~~~~~~~~~~~

• Subtask 1: 23 / 23
• Subtask 2: 20 / 20
• Subtask 3: 27 / 27
• Subtask 4: 30 / 30