Submission #1268700

#	Time	Username	Problem	Language	Result	Execution time	Memory
1268700		hoa208	Travelling Merchant (APIO17_merchant)	C++20	100 / 100	72 ms	2120 KiB

merchant

#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define FOR(i, a, b) for (int i = (a), _b = (b); i <= _b; i++)
#define FORD(i, b, a) for (int i = (b), _a = (a); i >= _a; i--)
#define pa pair<ll, ll>
#define fi first
#define se second
#define bit(mask, j) ((mask >> j) & 1)
const   ll mod = 1e9 + 7;
const   ll INF = 1e18;
//--------------------------------------------------------------------
const ll N = 103;
const ll K = 1003;
ll n, m, k;
vector<pa> g[N];
pa a[N][K];
ll dist[N][N], c[N][N], cost[N][N];
bool check(ll X) {
    memset(dist, -0x3f, sizeof dist);
    FOR(i, 1, n) {
        FOR(j, 1, n) {
            if(c[i][j] > INF) continue;
            dist[i][j] = cost[i][j] - X * c[i][j];
            // cout << i << ' ' << j << ' ' << dist[i][j] << '\n';
        }
    }
    FOR(k, 1, n) {
        FOR(u, 1, n) {
            FOR(v, 1, n) {
                if(dist[u][k] < -INF || dist[k][v] < -INF) continue;
                dist[u][v] = max(dist[u][v], dist[u][k] + dist[k][v]);
                // cout << u << ' ' << v << ' ' << dist[u][v] << '\n';
            }
        }
    }
    FOR(i, 1, n) {
        if(dist[i][i] >= 0) {
            return true;
        }
    }
    return false;
}
void hbmt() {
    cin >> n >> m >> k;
    FOR(i, 1, n) {
        FOR(j, 1, k) {
            ll s, b;
            cin >> b >> s;
            a[i][j] = {b, s};
        }
    }
    memset(c, 0x3f, sizeof c);
    FOR(i, 1, m) {
        ll u, v, w;
        cin >> u >> v >> w;
        c[u][v] = w;
    }
    FOR(i, 1, n) {
        FOR(j, 1, n) {
            FOR(u, 1, k) {
                if(a[i][u].fi != -1 && a[j][u].se != -1) {
                    cost[i][j] = max(cost[i][j], a[j][u].se - a[i][u].fi);
                }
            }
        }
    }
    FOR(k, 1, n) {
        FOR(u, 1, n) {
            FOR(v, 1, n) {
                c[u][v] = min(c[u][v], c[u][k] + c[k][v]);
            }
        }
    }
    // cout << c[1][1] << '\n';
    // cout << check(5) << '\n';
    // return;
    ll l = 1, r = 1e9;
    ll res = 0;
    while(l <= r) {
        ll mid = l + r >> 1;
        if(check(mid)) {
            l = mid + 1;
            res = mid;
        }
        else r = mid - 1;
    }
    cout << res;
}  

int main() {
    
    ios_base::sync_with_stdio(0);
    cin.tie(0);cout.tie(0);

    #define NAME "hbmt"
    if(fopen(NAME".inp", "r")) {
        freopen(NAME".inp", "r", stdin);
        freopen(NAME".out", "w", stdout);
    }
    
    //int t;cin>>t;while(t--)
    hbmt();
    return 0;
}

Compilation message (stderr)

merchant.cpp: In function 'int main()':
merchant.cpp:98:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   98 |         freopen(NAME".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
merchant.cpp:99:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   99 |         freopen(NAME".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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