Submission #197150

#	Time	Username	Problem	Language	Result	Execution time	Memory
197150		arnold518	Toll (BOI17_toll)	C++14	100 / 100	342 ms	69244 KiB

toll

#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

const int MAXN = 5e5;
const ll INF = 1e15;

int K, N, M, Q;
vector<pii> adj[MAXN+10];

struct Node
{
	vector<vector<ll>> V;
	Node() { V=vector<vector<ll>>(K, vector<ll>(K, INF)); }
};
Node Z;

Node operator + (const Node &p, const Node &q)
{
	Node ret=Node();
	int i, j, k;
	for(i=0; i<K; i++)
	{
		for(j=0; j<K; j++)
		{
			ll val=INF;
			for(k=0; k<K; k++) val=min(val, p.V[i][k]+q.V[k][j]);
			ret.V[i][j]=val;
		}
	}
	return ret;
}

Node tree[MAXN*4+10];

void init(int node, int tl, int tr)
{
	if(tl==tr)
	{
		int i, j;
		tree[node]=Node();
		for(i=(tl-1)*K; i<tl*K; i++) for(auto nxt : adj[i]) tree[node].V[i%K][nxt.first%K]=nxt.second;
		return;
	}
	int mid=tl+tr>>1;
	init(node*2, tl, mid);
	init(node*2+1, mid+1, tr);
	tree[node]=tree[node*2]+tree[node*2+1];
}

Node query(int node, int tl, int tr, int l, int r)
{
	if(l<=tl && tr<=r) return tree[node];
	if(tr<l || r<tl) return Z;
	int mid=tl+tr>>1;
	return query(node*2, tl, mid, l, r)+query(node*2+1, mid+1, tr, l, r);
}

int main()
{
	int i, j, k;
	scanf("%d%d%d%d", &K, &N, &M, &Q);
	if(N%K) N=N/K*K+K;

	Z=Node();
	for(i=0; i<K; i++) Z.V[i][i]=0;

	for(i=1; i<=M; i++)
	{
		int u, v, w;
		scanf("%d%d%d", &u, &v, &w);
		adj[u].push_back({v, w});
	}
	
	init(1, 1, N/K-1);
	while(Q--)
	{
		int a, b;
		scanf("%d%d", &a, &b);

		if(a/K==b/K) { printf("-1\n"); continue; }

		Node t=query(1, 1, N/K-1, a/K+1, b/K);
		ll ans=t.V[a%K][b%K];
		if(ans>=INF) ans=-1;
		printf("%lld\n", ans);
	}
}

Compilation message (stderr)

toll.cpp: In function 'void init(int, int, int)':
toll.cpp:43:10: warning: unused variable 'j' [-Wunused-variable]
   int i, j;
          ^
toll.cpp:48:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  int mid=tl+tr>>1;
          ~~^~~
toll.cpp: In function 'Node query(int, int, int, int, int)':
toll.cpp:58:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  int mid=tl+tr>>1;
          ~~^~~
toll.cpp: In function 'int main()':
toll.cpp:64:9: warning: unused variable 'j' [-Wunused-variable]
  int i, j, k;
         ^
toll.cpp:64:12: warning: unused variable 'k' [-Wunused-variable]
  int i, j, k;
            ^
toll.cpp:65:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d%d%d", &K, &N, &M, &Q);
  ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
toll.cpp:74:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d%d", &u, &v, &w);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~
toll.cpp:82:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d", &a, &b);
   ~~~~~^~~~~~~~~~~~~~~~

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