Submission #242741

#	Time	Username	Problem	Language	Result	Execution time	Memory
242741		SamAnd	Ferries (NOI13_ferries)	C++17	40 / 40	326 ms	18164 KiB

ferries

#include <bits/stdc++.h>
using namespace std;
#define m_p make_pair
#define all(x) (x).begin(),(x).end()
#define sz(x) ((int)(x).size())
#define fi first
#define se second
typedef long long ll;
mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());
mt19937 rnf(2106);
const int N = 100005;

int n, m;
vector<int> a[N], b[N];

struct ban
{
    int x, d;
    ban(){}
    ban(int x, int d)
    {
        this->x = x;
        this->d = d;
    }
};
bool operator<(const ban& a, const ban& b)
{
    return a.d > b.d;
}

bool c[N];

void solv()
{
    scanf("%d%d", &n, &m);
    while (m--)
    {
        int x, y, z;
        scanf("%d%d%d", &x, &y, &z);
        a[y].push_back(x);
        b[x].push_back(z);
    }
    for (int x = 1; x <= n; ++x)
    {
        sort(all(b[x]));
    }
    priority_queue<ban> q;
    q.push(ban(n, 0));
    while (1)
    {
        ban t;
        do
        {
            t = q.top();
            q.pop();
        } while (c[t.x]);
        c[t.x] = true;
        if (t.x == 1)
        {
            printf("%d\n", t.d);
            return;
        }
        for (int i = 0; i < a[t.x].size(); ++i)
        {
            ban h;
            h.x = a[t.x][i];
            h.d = t.d;
            h.d += b[h.x].back();
            b[h.x].pop_back();
            q.push(h);
        }
    }
}

int main()
{
    #ifdef SOMETHING
    freopen("input.txt", "r", stdin);
    //freopen("output.txt", "w", stdout);
    #endif // SOMETHING
    //ios_base::sync_with_stdio(false), cin.tie(0);
    solv();
    return 0;
}

//while ((double)clock() / CLOCKS_PER_SEC <= 0.9){}

Compilation message (stderr)

ferries.cpp: In function 'void solv()':
ferries.cpp:63:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0; i < a[t.x].size(); ++i)
                         ~~^~~~~~~~~~~~~~~
ferries.cpp:35:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d", &n, &m);
     ~~~~~^~~~~~~~~~~~~~~~
ferries.cpp:39:14: 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: 7 / 7
• Subtask 2: 10 / 10
• Subtask 3: 11 / 11
• Subtask 4: 12 / 12