Eddy's picture
Problem Description
Eddy begins to like painting pictures recently ,he is sure of himself to become a painter.Every day Eddy draws pictures in his small room, and he usually puts out his newest pictures to let his friends appreciate. but the result it can be imagined, the friends are not interested in his picture.Eddy feels very puzzled,in order to change all friends 's view to his technical of painting pictures ,so Eddy creates a problem for the his friends of you. Problem descriptions as follows: Given you some coordinates pionts on a drawing paper, every point links with the ink with the straight line, causes all points finally to link in the same place. How many distants does your duty discover the shortest length which the ink draws?
Input
The first line contains 0 < n <= 100, the number of point. For each point, a line follows; each following line contains two real numbers indicating the (x,y) coordinates of the point.
Input contains multiple test cases. Process to the end of file.
Input contains multiple test cases. Process to the end of file.
Output
Your program prints a single real number to two decimal places: the minimum total length of ink lines that can connect all the points.
Sample Input
3
1.0 1.0
2.0 2.0
2.0 4.0
Sample Output
3.41
prim算法:
#include<iostream>
#include<math.h>
using namespace std;
#define Max 100000
#include<string.h>
double flag[105][105];
int visit[105];
double ans[105];
struct lmx{
double x;
double y;
};
lmx lm[105];
double cnt(lmx s,lmx t)
{
return sqrt((s.x-t.x)*(s.x-t.x)+(s.y-t.y)*(s.y-t.y));
}
double prim(int n)
{
memset(visit,0,sizeof(visit));
int i,pos,k=n-1;
double min=Max;
visit[0]=1;
double sum=0;
memset(ans,Max,sizeof(ans));
for(i=1;i<n;i++)
{
ans[i]=flag[0][i];
}
while(k--)
{
min=Max;
for(i=0;i<n;i++)
{
if(visit[i]==0&&ans[i]<min)
{
min=ans[i];
pos=i;
}
}
visit[pos]=i;
sum+=min;
for(i=0;i<n;i++)
{
if(visit[i]==0&&flag[pos][i]<ans[i]) ans[i]=flag[pos][i];
}
}
return sum;
}
int main()
{
int n,i,j;
cout.precision(2);
while(cin>>n)
{
for(i=0;i<n;i++) cin>>lm[i].x>>lm[i].y;
for(i=0;i<n;i++)
{
for(j=0;j<n;j++)
{
if(i!=j) flag[i][j]=cnt(lm[i],lm[j]);
else flag[i][j]=Max;
}
}
cout<<fixed<<prim(n)<<endl;
}
return 0;
}
#include<math.h>
using namespace std;
#define Max 100000
#include<string.h>
double flag[105][105];
int visit[105];
double ans[105];
struct lmx{
double x;
double y;
};
lmx lm[105];
double cnt(lmx s,lmx t)
{
return sqrt((s.x-t.x)*(s.x-t.x)+(s.y-t.y)*(s.y-t.y));
}
double prim(int n)
{
memset(visit,0,sizeof(visit));
int i,pos,k=n-1;
double min=Max;
visit[0]=1;
double sum=0;
memset(ans,Max,sizeof(ans));
for(i=1;i<n;i++)
{
ans[i]=flag[0][i];
}
while(k--)
{
min=Max;
for(i=0;i<n;i++)
{
if(visit[i]==0&&ans[i]<min)
{
min=ans[i];
pos=i;
}
}
visit[pos]=i;
sum+=min;
for(i=0;i<n;i++)
{
if(visit[i]==0&&flag[pos][i]<ans[i]) ans[i]=flag[pos][i];
}
}
return sum;
}
int main()
{
int n,i,j;
cout.precision(2);
while(cin>>n)
{
for(i=0;i<n;i++) cin>>lm[i].x>>lm[i].y;
for(i=0;i<n;i++)
{
for(j=0;j<n;j++)
{
if(i!=j) flag[i][j]=cnt(lm[i],lm[j]);
else flag[i][j]=Max;
}
}
cout<<fixed<<prim(n)<<endl;
}
return 0;
}
为了明天所以选择坚定的执着今天。