克鲁斯卡尔算法用C++实现

以下是用C++实现克鲁斯卡尔算法的示例代码：

#include <bits/stdc++.h>
using namespace std;

const int MAXN = 1005;
int n, m, ans;
int fa[MAXN];

struct Edge {
    int u, v, w;
} e[MAXN * MAXN];

bool cmp(Edge a, Edge b) {
    return a.w < b.w;
}

int find(int x) {
    if (fa[x] == x) return x;
    return fa[x] = find(fa[x]);
}

void merge(int x, int y) {
    int fx = find(x), fy = find(y);
    if (fx != fy) fa[fx] = fy;
}

int main() {
    cin >> n >> m;
    for (int i = 1; i <= m; i++) {
        cin >> e[i].u >> e[i].v >> e[i].w;
    }
    sort(e + 1, e + m + 1, cmp);
    for (int i = 1; i <= n; i++) fa[i] = i;
    for (int i = 1; i <= m; i++) {
        int u = e[i].u, v = e[i].v, w = e[i].w;
        if (find(u) != find(v)) {
            merge(u, v);
            ans += w;
        }
    }
    cout << ans << endl;
    return 0;
}