Submission #197138

#	Time	Username	Problem	Language	Result	Execution time	Memory
197138		arnold518	Toll (BOI17_toll)	C++14	0 / 100	3094 ms	17660 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 = 5e4;
const ll INF = 1e15;

int K, N, M, Q;
map<int, ll> 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=0; i<K; i++) for(j=0; j<K; j++)
		{
			int p=(tl-1)*K+i, q=tl*K+j;
			if(adj[p].find(q)!=adj[p].end()) tree[node].V[i][j]=adj[p][q];
		}
		//printf("%d %d : \n", tl, tr);
		//for(i=0; i<K; i++) { for(j=0; j<K; j++) printf("%lld ", tree[node].V[i][j]); printf("\n"); }
		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];
	//int i, j;
	//printf("%d %d : \n", tl, tr);
	//for(i=0; i<K; i++) { for(j=0; j<K; j++) printf("%lld ", tree[node].V[i][j]); printf("\n"); }
}

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);
}

Node nodes[MAXN+10];

int main()
{
	int i, j, k;
	scanf("%d%d%d%d", &K, &N, &M, &Q);
	N=(N+K-1)/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][v]=w;
	}

	for(k=1; k<N/K; k++)
	{
		nodes[k]=Node();
		for(i=0; i<K; i++) for(j=0; j<K; j++)
		{
			int p=(k-1)*K+i, q=k*K+j;
			if(adj[p].find(q)!=adj[p].end()) nodes[k].V[i][j]=adj[p][q];
		}
	}

	//init(1, 1, N/K-1);
	while(Q--)
	{
		int a, b;
		scanf("%d%d", &a, &b);
		if(a/K==b/K) { printf("-1"); continue; }
		//Node t=query(1, 1, N/K-1, a/K+1, b/K);
		Node t=nodes[a/K+1];
		for(i=a/K+2; i<=b/K; i++) t=t+nodes[i];
		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:54:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  int mid=tl+tr>>1;
          ~~^~~
toll.cpp: In function 'Node query(int, int, int, int, int)':
toll.cpp:67:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  int mid=tl+tr>>1;
          ~~^~~
toll.cpp: In function 'int main()':
toll.cpp:76:7: 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:85:8: 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:103:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d", &a, &b);
   ~~~~~^~~~~~~~~~~~~~~~

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