nyoj--38 布线问题(最小生成树)

题解

#include <iostream>
#include <cstdio>
#include <vector>
#include <cstring>
#include <queue>
#include <algorithm>
using namespace std;

const int maxn = 500 + 10;
int   n, e;

struct Edge{
int u, v, c;
Edge(int u, int v, int c):u(u), v(v), c(c){}
};
vector<Edge> edges;
int p[maxn];

int find(int x) { return x == p[x] ? x : p[x] = find(p[x]); }
int cmp(const Edge& e1, const Edge& e2) { return e1.c < e2.c; }

int solve()
{
for(int i = 0; i <= n; ++i) p[i] = i;
sort(edges.begin(), edges.end(), cmp);

int ans = 0;
for(int i = 0; i < e; ++i)
{
int u = edges[i].u, v = edges[i].v, c = edges[i].c;
u = find(u), v = find(v);
if(u != v){
p[u] = v;
ans += c;
}
}
return ans;
}

int main()
{
//freopen("data.in", "r", stdin);
int t;

for(cin >> t; t--; )
{
edges.clear();
int a, b, c;
cin >> n >> e;
for(int i = 0; i < e; ++i){
scanf("%d %d %d", &a, &b, &c);
edges.push_back(Edge(a, b, c));
}
int maxcost = 1 << 30, tmp;
for(int i = 0; i < n; ++i){
scanf("%d", &tmp);
maxcost = min(maxcost, tmp);
}
cout << solve() + maxcost << endl;
}

return 0;
}