布线问题

#include <iostream>
#include <fstream>
#include <queue>
#include <cmath>
using namespace std;

const int INF = 100000;
int conn[21][21];  //连线矩阵
int n;             //元件个数
int bestx[21];     //解向量

class Node
{
public:
int dep;      //当前层
int val;      //布线费用
int *x;       //解向量

Node(int d, int val)
{
x = new int[n+1];
dep = d;
}

int getVal() //计算当前布线费用
{
int cur = 0;
for(int i=1; i<dep; i++) //计算布线成本
{
for(int j=i+1; j<=dep; j++)
cur += ( conn[i][j] * abs(x[j]-x[i]) );
}
return cur;
}

//布线费用小的先出队列
bool operator < (const Node &node) const
{
return val >= node.val;
}
};

int search()
{
priority_queue<Node> q;
Node enode(0, 0);
for(int j=1; j<=n; j++)
enode.x[j] = j;
int best = INF;
while(true)
{
if(enode.dep == n)
{
if(enode.val < best)
{
best = enode.val;
copy(enode.x, enode.x+n+1, bestx);
break;
}
}
else
{
for(int i=enode.dep+1; i<=n; i++)
{
Node now(enode.dep+1, 0);
copy(enode.x, enode.x+n+1, now.x);
now.x[now.dep] = enode.x[i];
now.x[i] = enode.x[now.dep];
now.val = now.getVal();
if(now.val < best)
q.push(now);
}
}
if(q.empty())
break;
else
{
enode = q.top();
q.pop();
}
}
return best;
}

int main()
{
ifstream fin("布线.txt");
cout << "元件数：";
fin >> n;   cout << n << endl;
cout << "输入元件之间连线数：\n";
for(int i=1; i<n; i++)
{
for(int j=i+1; j<=n; j++)
{
fin >> conn[i][j];
cout << conn[i][j] << " ";
}
cout << endl;
}

cout << "最小布线费用为：" << search() << endl;
cout << "布线方案为：\n";
for(i=1; i<=n; i++)
cout << bestx[i] << " ";
cout << endl;
cout << endl;
fin.close();
return 0;
}