oj.uz

답안 #161954

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
161954 2019-11-05T11:55:46 Z SamAnd Cities (BOI16_cities) C++17
100 / 100
 3684 ms 49880 KB 
#include <bits/stdc++.h>
using namespace std;
const int N = 100005, K = 5;
const long long INF = 1000000009000000009;
struct ban
{
    int x;
    long long d;
    ban(){}
    ban(int x, long long d)
    {
        this->x = x;
        this->d = d;
    }
};
bool operator<(const ban& a, const ban& b)
{
    return a.d > b.d;
}

int n, k, m;
int u[K];
vector<ban> a[N];

long long dp[N][1 << K];
bool c[N];
void djk(int x)
{
    memset(c, false, sizeof c);
    priority_queue<ban> q;
    for (int i = 1; i <= n; ++i)
        q.push(ban(i, dp[i][x]));
    while (1)
    {
        ban t;
        do
        {
            if (q.empty())
            {
                return;
            }
            t = q.top();
            q.pop();
        } while (c[t.x]);
        c[t.x] = true;
        dp[t.x][x] = t.d;
        for (int i = 0; i < a[t.x].size(); ++i)
        {
            ban h = a[t.x][i];
            h.d += t.d;
            if (!c[h.x])
                q.push(h);
        }
    }
}

int main()
{
    scanf("%d%d%d", &n, &k, &m);
    for (int i = 0; i < k; ++i)
        scanf("%d", &u[i]);
    for (int i = 0; i < m; ++i)
    {
        int x, y, z;
        scanf("%d%d%d", &x, &y, &z);
        a[x].push_back(ban(y, z));
        a[y].push_back(ban(x, z));
    }
    for (int x = 0; x < (1 << k); ++x)
    {
        for (int i = 1; i <= n; ++i)
            dp[i][x] = INF;
    }
    for (int x = 1; x < (1 << k); ++x)
    {
        int qq = 0, ii;
        for (int i = 0; i < k; ++i)
        {
            if ((x & (1 << i)))
            {
                ++qq;
                ii = i;
            }
        }
        if (qq == 1)
        {
            dp[u[ii]][x] = 0;
        }
        for (int i = 1; i <= n; ++i)
        {
            for (int y = 0; y < k; ++y)
            {
                if (!(x & (1 << y)))
                    continue;
                int z = (x ^ (1 << y));
                dp[i][x] = min(dp[i][x], dp[i][z] + dp[i][(1 << y)]);
            }
        }
        djk(x);
    }
    long long ans = INF;
    for (int i = 1; i <= n; ++i)
        ans = min(ans, dp[i][(1 << k) - 1]);
    printf("%lld\n", ans);
    return 0;
}

Compilation message

cities.cpp: In function 'void djk(int)':
cities.cpp:47:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0; i < a[t.x].size(); ++i)
                         ~~^~~~~~~~~~~~~~~
cities.cpp: In function 'int main()':
cities.cpp:59:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d%d", &n, &k, &m);
     ~~~~~^~~~~~~~~~~~~~~~~~~~~~
cities.cpp:61:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d", &u[i]);
         ~~~~~^~~~~~~~~~~~~
cities.cpp:65:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d%d", &x, &y, &z);
         ~~~~~^~~~~~~~~~~~~~~~~~~~~~

Subtask #1
22.0 / 22.0

# 결과 실행 시간 메모리 Grader output
1 Correct 5 ms 2936 KB Output is correct
2 Correct 4 ms 2808 KB Output is correct
3 Correct 5 ms 2808 KB Output is correct
4 Correct 5 ms 2808 KB Output is correct
5 Correct 5 ms 2808 KB Output is correct

Subtask #2
14.0 / 14.0

# 결과 실행 시간 메모리 Grader output
1 Correct 955 ms 49572 KB Output is correct
2 Correct 888 ms 49164 KB Output is correct
3 Correct 494 ms 39008 KB Output is correct
4 Correct 421 ms 22592 KB Output is correct
5 Correct 488 ms 49564 KB Output is correct
6 Correct 244 ms 22376 KB Output is correct
7 Correct 8 ms 3192 KB Output is correct
8 Correct 7 ms 3320 KB Output is correct

Subtask #3
15.0 / 15.0

# 결과 실행 시간 메모리 Grader output
1 Correct 12 ms 3192 KB Output is correct
2 Correct 11 ms 3320 KB Output is correct
3 Correct 9 ms 3192 KB Output is correct
4 Correct 11 ms 3064 KB Output is correct

Subtask #4
23.0 / 23.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1683 ms 49596 KB Output is correct
2 Correct 1623 ms 49180 KB Output is correct
3 Correct 1076 ms 39116 KB Output is correct
4 Correct 1312 ms 36996 KB Output is correct
5 Correct 882 ms 25416 KB Output is correct
6 Correct 796 ms 24756 KB Output is correct

Subtask #5
26.0 / 26.0

# 결과 실행 시간 메모리 Grader output
1 Correct 3420 ms 49880 KB Output is correct
2 Correct 3572 ms 49836 KB Output is correct
3 Correct 3684 ms 49260 KB Output is correct
4 Correct 2024 ms 39080 KB Output is correct
5 Correct 2354 ms 37268 KB Output is correct
6 Correct 1631 ms 25344 KB Output is correct
7 Correct 1542 ms 24900 KB Output is correct