Submission #114866

#	Time	Username	Problem	Language	Result	Execution time	Memory
114866		tinjyu	Highway Tolls (IOI18_highway)	C++14	5 / 100	199 ms	11224 KiB

highway

#include "highway.h"
#include <iostream>
using namespace std;

unsigned long long int m,p[1300005],amoney,bmoney,t,cnt,n,tag[1300005],road[1300005],map[2600005][2],sumlength,length,point,startans=-1,endans=-1,tree[1300005],trueroad,start=-1,a[1000005],father[1000005][2];
int check()
{
	vector<int> w(m);
	for(int i=0;i<m;i++)w[i]=p[i];
	for(int i=0;i<m;i++)p[i]=0;
	return ask(w);
}
int find(int s,int e)
{
	if(s==e)
	{
		start=s;
		return 0;
	}
	int mid=(s+e)/2;
	for(int i=s;i<=mid;i++)p[i]=1;
	t=check();
	if(t>cnt)find(s,mid);
	else find(mid+1,e);
}
int buildtree(int x)
{
	//cout<<x<<" ";
	int p=road[x];
	int c=0;
	while(p!=-1)
	{
		if(tag[map[p][0]]==0)
		{
			c=1;
			tag[map[p][0]]=1;
			father[map[p][0]][0]=x;
			father[map[p][0]][1]=p/2;
			buildtree(map[p][0]);
		}
		p=map[p][1];
	}
	if(c==0)
	{
		a[0]++;
		a[a[0]]=x;
	}
}
int findroad(int x)
{
	if(x==point || p[father[x][1]]==1)return 0;
	p[father[x][1]]=1;
	findroad(father[x][0]);
}
int findtwo(int s,int e)
{
	//cout<<"二分"<<s<<" "<<e<<endl;
	//for(int i=s;i<=e;i++)cout<<a[i]<<" ";
	//cout<<endl;
	if(s==e)
	{
		trueroad=a[s];
		findroad(a[s]);
		t=check();
		//cout<<"總花費"<<t<<" "<<cnt<<endl;
		length=(t-cnt)/(bmoney-amoney);
		return 0;
	}
	for(int i=s;i<=(s+e)/2;i++)
	{
		findroad(a[i]);
	}
	int l=check();
	if(l==cnt)findtwo((s+e)/2+1,e);
	for(int i=(s+e)/2+1;i<=e;i++)findroad(a[i]);
	int r=check();
	if(l>r)findtwo(s,(s+e)/2);
	else findtwo((s+e)/2+1,e);
}
int findlength(int x)
{
	//cout<<x<<endl;
	if(x==point)
	{
		return 0;
	}
	else
	{
		sumlength++;
		findlength(father[x][0]);
	}
}
int findans(int x)
{
	if(length==sumlength)
	{
		if(startans==-1)startans=x;
		else endans=x;
	}
	else
	{
		sumlength--;
		findans(father[x][0]);
	}
}
void find_pair(int N, std::vector<int> U, std::vector<int> V, int A, int B) {
	m = U.size();

	amoney=A;
	bmoney=B;
	n=N;
	for(int i=0;i<n;i++)road[i]=-1;
	for(int i=0;i<m;i++)
	{
		map[i*2][0]=V[i];
		map[i*2][1]=road[U[i]];
		road[U[i]]=i*2;
		map[i*2+1][0]=U[i];
		map[i*2+1][1]=road[V[i]];
		road[V[i]]=i*2+1;
	}
	
	for(int i=0;i<m;i++)p[i]=0;
	cnt=check();
	find(0,m-1);
	tag[V[start]]=1;
	tag[U[start]]=1;
	point=U[start];

	buildtree(point);
	//cout<<endl;
	//cout<<point<<endl;
	//for(int i=1;i<=a[0];i++)cout<<a[i]<<" ";
	//cout<<endl;
	findtwo(1,a[0]);
	findlength(trueroad);
	//cout<<sumlength<<" "<<length<<" "<<trueroad<<endl;

	findans(trueroad);
	
	
	
	point=V[start];
	a[0]=0;
	tag[point]=1;
	sumlength=0;
	buildtree(point);
	//cout<<endl;
	//cout<<point<<endl;
	//for(int i=1;i<=a[0];i++)cout<<a[i]<<" ";
	//cout<<endl;
	findtwo(1,a[0]);
	findlength(trueroad);
	//cout<<sumlength<<" "<<length<<" "<<trueroad<<endl;

	findans(trueroad);
	//cout<<startans<<" "<<endans<<endl;
	answer(startans,endans);
}

Compilation message (stderr)

highway.cpp: In function 'int check()':
highway.cpp:9:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<m;i++)w[i]=p[i];
              ~^~
highway.cpp:10:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<m;i++)p[i]=0;
              ~^~
highway.cpp: In function 'int buildtree(int)':
highway.cpp:48:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
highway.cpp: In function 'int findroad(int)':
highway.cpp:51:6: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  if(x==point || p[father[x][1]]==1)return 0;
     ~^~~~~~~
highway.cpp: In function 'int findtwo(int, int)':
highway.cpp:74:6: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  if(l==cnt)findtwo((s+e)/2+1,e);
     ~^~~~~
highway.cpp: In function 'int findlength(int)':
highway.cpp:83:6: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  if(x==point)
     ~^~~~~~~
highway.cpp: In function 'int findans(int)':
highway.cpp:97:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   if(startans==-1)startans=x;
      ~~~~~~~~^~~~
highway.cpp:105:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
highway.cpp: In function 'void find_pair(int, std::vector<int>, std::vector<int>, int, int)':
highway.cpp:112:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<n;i++)road[i]=-1;
              ~^~
highway.cpp:113:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<m;i++)
              ~^~
highway.cpp:123:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<m;i++)p[i]=0;
              ~^~
highway.cpp: In function 'int find(int, int)':
highway.cpp:25:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^
highway.cpp: In function 'int findroad(int)':
highway.cpp:54:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^
highway.cpp: In function 'int findtwo(int, int)':
highway.cpp:79:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^
highway.cpp: In function 'int findlength(int)':
highway.cpp:92:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^

• Subtask 1: 5 / 5
• Subtask 2: 0 / 7
• Subtask 3: 0 / 6
• Subtask 4: 0 / 33
• Subtask 5: 0 / 18
• Subtask 6: 0 / 31