Submission #698893

#	Time	Username	Problem	Language	Result	Execution time	Memory
698893		nguyentunglam	Travelling Merchant (APIO17_merchant)	C++17	0 / 100	1088 ms	3088 KiB

merchant

#include<bits/stdc++.h>
#define fi first
#define se second
#define endl "\n"
#define ii pair<int, int>
using namespace std;
const int M = 1010, N = 110;
int s[N][N], b[N][N];
int n, m, k;
int cnt[2][M][N];
long long f[2][M][N];
bool in[2][M][N];
queue<tuple<int, int, int> > q;
vector<pair<int, int> > adj[N];
bool check(int mid) {
    for(int i = 1; i <= n; i++) {
        memset(f, -127, sizeof(f));
        memset(cnt, 0, sizeof(cnt));
        f[0][0][i] = 0;
        q.push({0, 0, i});
        while (!q.empty()) {
            auto [exit, carry, u] = q.front(); q.pop();
            in[exit][carry][u] = 0;
            cnt[exit][carry][u]++;
//            cerr << exit << " " << carry << " " << u << " " << f[exit][carry][u] << endl;
            if (cnt[exit][carry][u] >= 20) return 1;
            if (carry) {
                if (s[u][carry] != -1 && f[exit][0][u] < f[exit][carry][u] + s[u][carry]) {
                    f[exit][0][u] = f[exit][carry][u] + s[u][carry];
                    if (!in[exit][0][u]) q.push({exit, 0, u}), in[exit][0][u] = 1;
                }
            }
            if (!carry) {
                for(int j = 1; j <= k; j++) {
//                    if (exit == 1 && carry == 0 && u == 4) cerr << b[u][j] << " " << f[exit][carry][u] - b[u][j] << endl;
                    if (b[u][j] != -1 && f[exit][j][u] < f[exit][carry][u] - b[u][j]) {
                        f[exit][j][u] = f[exit][carry][u] - b[u][j];
                        if (!in[exit][j][u]) q.push({exit, j, u}), in[exit][j][u] = 1;
                    }
                }
            }
            for(auto &[v, w] : adj[u]) {
                int _e = exit | 1;
//                if (_e && carry == 1 && v == 4) cerr << u << " " << f[exit][carry][u] << endl;
                if (f[_e][carry][v] < f[exit][carry][u] - 1LL * w * mid) {
                    f[_e][carry][v] = f[exit][carry][u] - 1LL * w * mid;
                    if (!in[_e][carry][v]) q.push({_e, carry, v}), in[exit][carry][v] = 1;
                }
            }
        }
        if (f[1][0][i] >= 0) return 1;
    }
    return 0;
}
int main() {
    #define task ""
    cin.tie(0) -> sync_with_stdio(0);
    if (fopen ("task.inp", "r")) {
        freopen ("task.inp", "r", stdin);
        freopen ("task.out", "w", stdout);
    }
    if (fopen (task".inp", "r")) {
        freopen (task".inp", "r", stdin);
        freopen (task".out", "w", stdout);
    }
    cin >> n >> m >> k;
    for(int i = 1; i <= n; i++) for(int j = 1; j <= k; j++) cin >> b[i][j] >> s[i][j];
    while (m--) {
        int u, v, w; cin >> u >> v >> w;
        adj[u].emplace_back(v, w);
    }
    int l = 1, r = 1e9, res = 0;
    while (l <= r) {
        int mid = l + r >> 1;
        if (check(mid)) {
            l = mid + 1;
            res = mid;
        }
        else r = mid - 1;
    }
    cout << res;
}

Compilation message (stderr)

merchant.cpp: In function 'int main()':
merchant.cpp:74:21: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   74 |         int mid = l + r >> 1;
      |                   ~~^~~
merchant.cpp:59:17: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   59 |         freopen ("task.inp", "r", stdin);
      |         ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
merchant.cpp:60:17: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   60 |         freopen ("task.out", "w", stdout);
      |         ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
merchant.cpp:63:17: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   63 |         freopen (task".inp", "r", stdin);
      |         ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
merchant.cpp:64:17: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   64 |         freopen (task".out", "w", stdout);
      |         ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 12
• Subtask 2: 0 / 21
• Subtask 3: 0 / 33
• Subtask 4: 0 / 34