Submission #399090

#	Time	Username	Problem	Language	Result	Execution time	Memory
399090		cpp219	Travelling Merchant (APIO17_merchant)	C++14	100 / 100	106 ms	5388 KiB

merchant

#pragma GCC optimization "O2"
#pragma GCC optimization "unroll-loop"
#pragma GCC target ("avx2")

#include<bits/stdc++.h>
#define ll long long
#define ld long double
#define fs first
#define sc second
using namespace std;
typedef pair<ll,ll> LL;
const ll N = 1e3 + 9;
const ll inf = 1e15 + 7;

ll profit[N][N],n,m,d[N][N],B[N][N],S[N][N],adj[N][N];
ll x,y,w,k;

void out(){
    for (ll i = 1;i <= n;i++){
        for (ll j = 1;j <= n;j++) cout<<adj[i][j]<<" ";
        cout<<"\n";
    }
    exit(0);
}

bool chk(ll x){
    if (!x) return 1;
    for (ll i = 1;i <= n;i++){
        for (ll j = 1;j <= n;j++){
            if (i == j) adj[i][j] = -inf;
            else{
                if (d[i][j] > inf/x) adj[i][j] = -inf;
                else adj[i][j] = profit[i][j] - x*d[i][j];
            }
        }
    }
    //out();
    for (ll l = 1;l <= n;l++){
        for (ll i = 1;i <= n;i++){
            for (ll j = 1;j <= n;j++) adj[i][j] = max(adj[i][j],adj[i][l] + adj[l][j]);
        }
    }
    for (ll i = 1;i <= n;i++) if (adj[i][i] >= 0) return 1;
    return 0;
}

int main(){
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    #define task "test"
    if (fopen(task".inp","r")){
        freopen(task".inp","r",stdin);
        //freopen(task".out","w",stdout);
    }
    cin>>n>>m>>k;
    for (ll i = 1;i <= n;i++)
        for (ll j = 1;j <= k;j++) cin>>B[i][j]>>S[i][j];
    for (ll i = 1;i <= n;i++)
        for (ll j = 1;j <= n;j++) d[i][j] = inf;
    while(m--){
        cin>>x>>y>>w;
        d[x][y] = w;
    }
    for (ll l = 1;l <= n;l++)
        for (ll i = 1;i <= n;i++)
            for (ll j = 1;j <= n;j++) d[i][j] = min(d[i][j],d[i][l] + d[l][j]);
    for (ll i = 1;i <= n;i++){
        for (ll j = 1;j <= n;j++){
            if (i == j||d[i][j] == inf) continue;
            ll now = 0;
            for (ll l = 1;l <= k;l++)
                if (S[j][l] != -1 && B[i][l] != -1) now = max(now,S[j][l] - B[i][l]);
            profit[i][j] = now;
        }
    }
    ll l,mid,h; //cout<<chk(2); return 0;
    l = 0; h = inf;
    while(l <= h){
        mid = (l + h)/2;
        if (chk(mid)) l = mid + 1;
        else h = mid - 1;
    }
    cout<<h;
}

Compilation message (stderr)

merchant.cpp:1: warning: ignoring #pragma GCC optimization [-Wunknown-pragmas]
    1 | #pragma GCC optimization "O2"
      | 
merchant.cpp:2: warning: ignoring #pragma GCC optimization [-Wunknown-pragmas]
    2 | #pragma GCC optimization "unroll-loop"
      | 
merchant.cpp: In function 'int main()':
merchant.cpp:51:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   51 |         freopen(task".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

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