Submission #1285111

#	Time	Username	Problem	Language	Result	Execution time	Memory
1285111		longdeptrai	Toll (BOI17_toll)	C++20	8 / 100	3094 ms	7024 KiB

toll

#include <bits/stdc++.h>
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
//using namespace __gnu_pbds;
#define LongDepTrai "toll"
#define ll long long
#define ull unsigned long long
#define ld long double
#define ii pair<int,int>
#define iii pair<int,ii>
#define iv pair<ii,ii>
#define pll pair<ll,ll>
#define vi vector<int>
#define vii vector<ii>
#define vll vector<ll>
#define fi first
#define se second
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define sz(x) int((x).size())
#define order_set(T) tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>

inline ll add(ll a, ll b, ll mod){ a += b; if(a >= mod) a -= mod; return a; }
inline ll sub(ll a, ll b, ll mod){ a -= b; if(a < 0) a += mod; return a; }
inline ll mul(ll a, ll b, ll mod){ return ( (ll)a * b ) % mod; }

static mt19937_64 rng((unsigned)chrono::steady_clock::now().time_since_epoch().count());
const int N=5e4+9;
int n,o,k,m,t,f[N],vs[N];
vii g[N];
vector<int> toco;
void dfs(int u){
    vs[u]=1;
    for(ii v:g[u]){
        if(!vs[v.fi]) dfs(v.fi);
    }
    vs[u]=2;
    toco.pb(u);
}

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

    if(fopen(LongDepTrai".inp","r")){
        freopen(LongDepTrai".inp","r",stdin);
        freopen(LongDepTrai".out","w",stdout);
    }
    cin>>k>>n>>m>>o;

    for(int i=1;i<=m;i++){
        int u,v,w;
        cin>>u>>v>>w;
        g[u].pb({v,w});
    }
    for(int i=1;i<=n;i++){
        f[i]=2e9;
    }
    for(int i=1;i<=o;i++){
        int u,v;
        cin>>u>>v;
        toco.clear();
        for(int j=1;j<=n;j++){
            vs[j]=0;
            f[j]=2e9;
        }
        dfs(u);
        f[u]=0;
        reverse(toco.begin(),toco.end());
        for(int x:toco){
          //  cout<<x<<" ";
            for(ii l:g[x]){
                f[l.fi]=min(f[l.fi],f[x]+l.se);
            }

        }
        if(f[v]==2e9) cout<<-1<<"\n";
        else
        cout<<f[v]<<"\n";
    }
    return 0;
}

Compilation message (stderr)

toll.cpp: In function 'int main()':
toll.cpp:47:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   47 |         freopen(LongDepTrai".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
toll.cpp:48:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   48 |         freopen(LongDepTrai".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 7
• Subtask 2: 0 / 10
• Subtask 3: 8 / 8
• Subtask 4: 0 / 31
• Subtask 5: 0 / 44