Submission #1217051

#	Time	Username	Problem	Language	Result	Execution time	Memory
1217051		InvMOD	Travelling Merchant (APIO17_merchant)	C++17	100 / 100	83 ms	1348 KiB

merchant

#include<bits/stdc++.h>

using namespace std;

#define fi first
#define se second
#define pb push_back
#define eb emplace_back

#define vi vector<int>
#define pi pair<int,int>
#define sz(v) (int)(v).size()
#define all(v) (v).begin(), (v).end()
#define compact(v) (v).erase(unique(all(v)), (v).end())

template<class T> using upq = priority_queue<T, vector<T>, greater<T>>;
template<class T> int lwrbound(const vector<T>& a, const T& b, const int s = 0){return int(lower_bound(s + all(a), b) - a.begin());}
template<class T> int uprbound(const vector<T>& a, const T& b, const int s = 0){return int(upper_bound(s + all(a), b) - a.begin());}

#define FOR(i, a, b) for(int i = (a); i <= (b); i++)
#define ROF(i, a, b) for(int i = (a); i >= (b); i--)
#define sumof(x) accumulate(all(x), 0ll)
#define dbg(x) "[" << #x " = " << (x) << "]"
#define el "\n"

using ll = long long;
using ld = long double;

template<class T> bool ckmx(T& a, const T b){return (a < b ? a = b, true : false);}
template<class T> bool ckmn(T& a, const T b){return (a > b ? a = b, true : false);}

const ll INF = 1e15;


void Main()
{
    int n,m,k; cin >> n >> m >> k;

    vector<vi> b(n + 1, vi(k + 1)), s(n + 1, vi(k + 1));
    FOR(i, 1, n){
        FOR(j, 1, k){
            cin >> b[i][j] >> s[i][j];
        }
    }

    vector<vector<ll>> profit(n + 1, vector<ll>(n + 1));
    FOR(i, 1, n){
        FOR(j, 1, n){
            FOR(x, 1, k){
                if(s[j][x] == -1 || b[i][x] == -1) continue;
                ckmx(profit[i][j], 1ll * s[j][x] - b[i][x]);
            }
        }
    }

    vector<vector<ll>> d(n + 1, vector<ll>(n + 1, INF));
    FOR(i, 1, m){
        int u,v,w; cin >> u >> v >> w;

        ckmn(d[u][v], 1ll * w);
    }

    FOR(k, 1, n){
        FOR(u, 1, n){
            FOR(v, 1, n){
                ckmn(d[u][v], d[u][k] + d[k][v]);
            }
        }
    }

    vector<vector<ll>> dp(n + 1, vector<ll>(n + 1, INF));
    auto good = [&](ll eff) -> bool{
        // sum profit / time = eff => sum profit >= time * eff

        FOR(u, 1, n){
            FOR(v, 1, n){
                if(u == v) dp[u][v] = INF;
                else{
                    dp[u][v] = (d[u][v] == INF ? INF : d[u][v] * eff);
                }
                dp[u][v] = -dp[u][v] + profit[u][v];

//                if(dp[u][v] > 0){
//                    cout << u <<" " << v << " " << d[u][v] <<" " << profit[u][v] << el;
//                }
            }
        }

        FOR(k, 1, n){
            FOR(u, 1, n){
                FOR(v, 1, n){
                    ckmx(dp[u][v], dp[u][k] + dp[k][v]);
                }
            }
        }

        FOR(i, 1, n) if(dp[i][i] >= 0) return true;
        return false;
    };

    //cout << good(2) << el; return;

    int l = 0, r = 1e9;
    while(l + 1 < r){
        int m = l + r >> 1;
        (good(m) ? l = m : r = m);
    }

    cout << l << el;
}

int32_t main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);

    #define name "InvMOD"
    if(fopen(name".INP", "r")){
        freopen(name".INP", "r", stdin);
        freopen(name".OUT", "w", stdout);
    }

    int t = 1; while(t--) Main();
    return 0;
}

Compilation message (stderr)

merchant.cpp: In function 'int32_t main()':
merchant.cpp:119:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  119 |         freopen(name".INP", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
merchant.cpp:120:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  120 |         freopen(name".OUT", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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