Submission #355529

#	Time	Username	Problem	Language	Result	Execution time	Memory
355529		codebuster_10	Toll (BOI17_toll)	C++17	100 / 100	198 ms	28764 KiB

toll

#include <bits/stdc++.h>

using namespace std ;

#define i64 int64_t // typecast using i64(x)
#define int int64_t 
#define ld long double
#define f(i,a,b) for(int i=a; i<b; ++i)
#define endl '\n'

#define PQ priority_queue
#define LB lower_bound  
#define UB upper_bound
#define fr first
#define sc second

#define all(a) (a).begin(),(a).end()
#define allr(a) (a).rbegin(),(a).rend()
#define sz(x) ((int)(x).size())

//#ifndef ONLINE_JUDGE
template<typename T>
void __p(T a) {
  cout<<a; 
}
template<typename T, typename F>
void __p(pair<T, F> a) {
  cout<<"{";
  __p(a.first);
  cout<<",";
  __p(a.second);
  cout<<"}\n"; 
}
template<typename T>
void __p(std::vector<T> a) {
  cout<<"{";
  for(auto it=a.begin(); it<a.end(); it++)
    __p(*it),cout<<",}\n"[it+1==a.end()]; 
}
template<typename T, typename ...Arg>
void __p(T a1, Arg ...a) {
  __p(a1);
  __p(a...);
}
template<typename Arg1>
void __f(const char *name, Arg1 &&arg1) {
  cout<<name<<" : ";
  __p(arg1);
  cout<<endl;
}
template<typename Arg1, typename ... Args>
void __f(const char *names, Arg1 &&arg1, Args &&... args) {
  int bracket=0,i=0;
  for(;; i++)
    if(names[i]==','&&bracket==0)
      break;
    else if(names[i]=='(')
      bracket++;
    else if(names[i]==')')
      bracket--;
  const char *comma=names+i;
  cout.write(names,comma-names)<<" : ";
  __p(arg1);
  cout<<" | ";
  __f(comma+1,args...);
}
//#endif

void setIO(string s = "") {
  ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); 
  cin.exceptions(cin.failbit); 
  if(sz(s)){
    freopen((s+".in").c_str(),"r",stdin);
    freopen((s+".out").c_str(),"w",stdout);
  }
}
void solve(){
  
}
const int INF = 1e12 ;
signed main(){
  setIO() ;
  int K, N, M, O; cin >> K >> N >> M >> O ;
  int LOG = log2(N) + 1 ;
  int dis[N][K][LOG] ; 
  
  f(i,0,N) f(j,0,K) f(k,0,LOG) dis[i][j][k] = INF ;

  f(_,0,M){
    int a, b, t; cin >> a >> b >> t ;
    dis[a][b%K][0] = t ;
  }
  f(k,1,LOG){
    f(i,0,N){
      f(j,0,K){
        f(u,0,K){
          int mid = K * ( i/K + (1 << (k-1)) ) + u ; 
          if(mid >= N) continue ;
          dis[i][j][k] = min(dis[i][j][k], dis[i][u][k-1] + dis[mid][j][k-1]) ;
        }
      }
    }
  }
  
  /*f(i,0,N) f(j,0,K) f(k,0,LOG){
    __f("i,j,k,dis[i][j][k]",i,j,k,dis[i][j][k]) ;
  } */
  
  while(O--){
    int a, b; cin >> a >> b ; assert(a != b) ;
    int d = b/K - a/K ;
    if(d <= 0){ cout << "-1" << endl ; continue ;}
    d--;
    
    vector<int> cur(K), D(K) ;
    f(i,0,K){
      cur[i] = K * (a/K + 1) + i ;
      D[i] = dis[a][i][0] ;
    }
    //__f("d,cur,D",d,cur,D) ;
    for(int k = LOG-1; k >= 0 ; --k){
      if( (1 << k) <= d){
        vector<int> newD(K,INF) ;
        
        f(i,0,K){  // we reach at j from i
          // what this i updates ;
          f(j,0,K){ 
            if(cur[i] >= N) continue  ;
            newD[j] = min(newD[j], dis[cur[i]][j][k] + D[i] ) ;
          }  
        }
        
        int Q = cur[0]/K ;
        f(i,0,K) cur[i] =  K * ( Q + (1 << k) ) + i ;
        
        D = newD ;
        d -= (1 << k) ;
      }
    }
    assert(cur[b%K] == b) ;
    if( D[b%K] >= INF){
      cout << "-1" << endl ; continue ;
    }
    cout << D[b%K] << endl ;
  }
}

Compilation message (stderr)

toll.cpp: In function 'void setIO(std::string)':
toll.cpp:74:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   74 |     freopen((s+".in").c_str(),"r",stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
toll.cpp:75:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   75 |     freopen((s+".out").c_str(),"w",stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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