Submission #1093569

#	Time	Username	Problem	Language	Result	Execution time	Memory
1093569		Thanhs	Toll (BOI17_toll)	C++14	100 / 100	88 ms	82004 KiB

toll

#include <bits/stdc++.h>
using namespace std;

#define fi first
#define se second
// #define int long long
#define endl '\n'
#define setmin(x, y) x = ((x) < (y) ? (x) : (y))
#define setmax(x, y) x = ((x) > (y) ? (x) : (y))

mt19937 hdp(chrono::high_resolution_clock::now().time_since_epoch().count());
int rand(int l, int r){return l + ((hdp() % (r - l + 1)) + r - l + 1) % (r - l + 1);}

const int NM = 5e4 + 5;
const int LG = 16;
const int inf = 1e9;

int n, m, q, k;

struct node
{
    int dt[5][5];
    node() {for (int i = 0; i < 5; i++) for (int j = 0; j < 5; j++) dt[i][j] = inf;}
    node operator*(const node& o)
    {
        node res;
        for (int i = 0; i < k; i++)
            for (int j = 0; j < k; j++)
                for (int t = 0; t < k; t++)
                    setmin(res.dt[i][j], dt[i][t] + o.dt[t][j]);
        return res;
    }
}st[NM][LG];

void solve()    
{
    cin >> k >> n >> m >> q;
    for (int i = 1; i <= m; i++)
    {
        int u, v, w;
        cin >> u >> v >> w;
        setmin(st[u / k][0].dt[u % k][v % k], w);
    }
    for (int lg = 1; lg <= __lg(n / k + 1); lg++)
        for (int i = 0; i + (1 << lg) - 1 < n / k; i++)
            st[i][lg] = st[i][lg - 1] * st[i + (1 << lg - 1)][lg - 1];
    while (q--)
    {
        int u, v;
        cin >> u >> v;
        if (u == v)
            cout << 0 << endl;
        else if (u / k < v / k)
        {
            int x = v / k - u / k;
            node res = st[u / k][__lg(x)];
            int t = x - (1 << __lg(x)), cur = u / k + (1 << __lg(x));
            for (int i = t ? __lg(t) : -1; i >= 0; i--)
                if (t & (1 << i))
                {
                    res = res * st[cur][i];
                    cur += 1 << i;
                }
            cout << (res.dt[u % k][v % k] == inf ? -1 : res.dt[u % k][v % k]) << endl;
        }
        else
            cout << -1 << endl;
    }
}

signed main()
{
    ios_base::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);
    if (fopen("in.txt", "r")) 
    {
        freopen("in.txt", "r", stdin);
        freopen("out.txt", "w", stdout);
    }
    // freopen("storagebox.inp", "r", stdin);
    // freopen("storagebox.out", "w", stdout);
    int tc = 1; 
    // cin >> tc;
    while (tc--)
        solve();
}

Compilation message (stderr)

toll.cpp: In function 'void solve()':
toll.cpp:46:57: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   46 |             st[i][lg] = st[i][lg - 1] * st[i + (1 << lg - 1)][lg - 1];
      |                                                      ~~~^~~
toll.cpp: In function 'int main()':
toll.cpp:76:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   76 |         freopen("in.txt", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
toll.cpp:77:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   77 |         freopen("out.txt", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 7 / 7
• Subtask 2: 10 / 10
• Subtask 3: 8 / 8
• Subtask 4: 31 / 31
• Subtask 5: 44 / 44