很神奇的一道題。。知道是生成樹後就好做了
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <vector>
using namespace std;
const int mx = 1005;
const int INF = 0x3f3f3f3f;
int n, m, w, vis[mx], dis[mx];
char word[mx][12];
vector <pair<int,int> > G[mx];
int prim(int u)
{
memset(vis, false, sizeof(vis));
for (int i = G[u].size()-1; i >= 0; i--)
dis[G[u][i].first] = G[u][i].second;
vis[u] = true;
int index, sum = 0;
for (int i = 1; i < n; i++)
{
int minidis = INF;
for (int j = 1; j <= n; j++)
{
if (!vis[j] && dis[j] < minidis)
{
index = j;
minidis = dis[j];
}
}
vis[index] = true;
sum += minidis;
for (int j = G[index].size()-1; j >= 0; j--)
{
int v = G[index][j].first;
int dist = G[index][j].second;
if (!vis[v] && dis[v] > dist)
dis[v] = dist;
}
}
return sum;
}
void init()
{
for (int i = 0; i < mx; i++)
G[i].clear();
memset(dis, 0x3f, sizeof(dis));
}
int main()
{
while (scanf("%d%d%d",&n,&m,&w) != EOF)
{
init();
for (int i = 1; i <= n; i++)
scanf("%s",word[i]);
for (int i = 1; i <= n; i++)
{
for (int j = i+1; j <= n; j++)
{
int hanming = 0, dist;
for (int k = 0; k < m; k++)
if (word[i][k] != word[j][k])
hanming++;
dist = min(hanming*w,m);
G[i].push_back(make_pair(j,dist));
G[j].push_back(make_pair(i,dist));
}
}
printf("%d\n",m+prim(1));
}
return 0;
}