Submission #200327

#	Time	Username	Problem	Language	Result	Execution time	Memory
200327		BThero	Travelling Merchant (APIO17_merchant)	C++17	0 / 100	1090 ms	2428 KiB

merchant

// Why am I so dumb? :c
// chrono::system_clock::now().time_since_epoch().count()
                                                  
#include<bits/stdc++.h>
//#include<ext/pb_ds/assoc_container.hpp>
//#include<ext/pb_ds/tree_policy.hpp>
 
#define pb push_back
#define mp make_pair
 
#define all(x) (x).begin(), (x).end()
 
#define fi first
#define se second
 
using namespace std;
//using namespace __gnu_pbds;
 
typedef long long ll;   
typedef pair<int, int> pii;
//template<typename T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
 
const int MAXN = (int)1e2 + 5;
const int MAXK = (int)1e3 + 5;
const ll LINF = (ll)1e17;
 
int buy[MAXN][MAXK], sell[MAXN][MAXK];
 
ll dp[MAXN][MAXK];
 
int adj[MAXN][MAXN];
 
int n, m, k;
 
bool check(int x) {
    for (int st = 1; st <= n; ++st) {
        for (int i = 1; i <= n; ++i) {
            for (int j = 0; j <= k; ++j) {
                dp[i][j] = -LINF;
            }
        }

        queue<pii> q;
 
        for (int to = 1; to <= n; ++to) {
            if (adj[st][to] == -1) {
                continue;
            }
            
            ll w = adj[st][to] * 1ll * x;
            dp[to][0] = -w;
            q.push(mp(to, 0));
 
            for (int i = 1; i <= k; ++i) {
                if (buy[st][i] != -1) {
                    dp[to][i] = -w - buy[st][i];
                    q.push(mp(to, i));
                }
            }                                                            
        }
 
        while (!q.empty()) {
            int v = q.front().fi;
            int j = q.front().se;
            q.pop();

            if (dp[st][0] >= 0) {
                return 1;
            }

            if (j == 0) {
                for (int i = 1; i <= k; ++i) {
                    if (buy[v][i] != -1) {
                        ll cur = dp[v][j] - buy[v][i];

                        if (cur > dp[v][i]) {
                            dp[v][i] = cur;
                            q.push(mp(v, i));                                                   
                        }
                    }                
                }
            }
            else {
                if (sell[v][j] != -1) {
                    ll cur = dp[v][j] + sell[v][j];

                    if (cur > dp[v][0]) {
                        dp[v][0] = cur;
                        q.push(mp(v, 0));
                    }
                }
            }
            
            for (int to = 1; to <= n; ++to) {
                if (adj[v][to] != -1) {
                    ll w = adj[v][to] * 1ll * x;

                    if (dp[v][j] - w > dp[to][j]) {
                        dp[to][j] = dp[v][j] - w;
                        q.push(mp(to, j));
                    }
                }
            }
        } 
    }
 
    return 0; 
}
 
void solve() {
    scanf("%d %d %d", &n, &m, &k);
 
    for (int i = 1; i <= n; ++i) {
        for (int j = 1; j <= k; ++j) {
            scanf("%d %d", &buy[i][j], &sell[i][j]);
        }
    }
 
    for (int i = 1; i <= n; ++i) {
        for (int j = 1; j <= n; ++j) {
            adj[i][j] = -1;
        }
    }
 
    for (int i = 1; i <= m; ++i) {
        int u, v, w;
        scanf("%d %d %d", &u, &v, &w);
        adj[u][v] = w;
    }
 
    int l = 1, r = (int)1e9, ans = 0;
 
    while (l <= r) {
        int mid = (l + r) >> 1;
 
        if (check(mid)) {
            l = mid + 1;
            ans = mid;
        }
        else {
            r = mid - 1;
        }
    }
 
    printf("%d\n", ans);
}
 
int main() {
    int tt = 1;
 
    while (tt--) {
        solve();
    }
 
    return 0;
}

Compilation message (stderr)

merchant.cpp: In function 'void solve()':
merchant.cpp:111:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d %d", &n, &m, &k);
     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
merchant.cpp:115:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
             scanf("%d %d", &buy[i][j], &sell[i][j]);
             ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
merchant.cpp:127:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d %d %d", &u, &v, &w);
         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

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