模板：Prime最小生成树堆优化 + Dijkstra单源最短路堆优化

Dijkstra 单源最短路堆优化

#include<bits/stdc++.h>
using namespace std;
typedef pair<int, int> PII;
const int N = 2e5 + 10;
int head[N], to[N], value[N], nex[N], cnt = 1;
int n, m, rt, st, dis[N], visit[N];
struct cmp {
	bool operator()(PII a, PII b) {
		return a.second > b.second;
	}
};
void add(int x, int y, int w) {
	to[cnt] = y;
	nex[cnt] = head[x];
	value[cnt] = w;
	head[x] = cnt++;
}
void Dijkstra() {
	memset(dis, 0x3f, sizeof dis);
	dis[rt] = 0;
	priority_queue<PII, vector<PII>, cmp> q;
	q.push(make_pair(rt, 0));
	while(!q.empty()) {
		int p = q.top().first;
		q.pop();
		if(visit[p])	continue;
		visit[p] = 1;
		for(int i = head[p]; i; i = nex[i]) {
			if(dis[to[i]] > dis[p] + value[i]) {
				dis[to[i]] = dis[p] + value[i];
				q.push(make_pair(to[i], dis[p] + value[i]));
			}
		}
	}
	for(int i = 1; i <= n; i++)
		printf("%d%c", dis[i] == 0x3f3f3f3f ? (int)((1ll << 31) - 1) : dis[i], i == n ? '\n' : ' ');
}
int main() {
	int x, y, w;
	scanf("%d %d %d", &n, &m, &rt);
	for(int i = 0; i < m; i++) {
		scanf("%d %d %d", &x, &y, &w);
		add(x, y, w);
	}
	Dijkstra();
	return 0;
}

Prime 最小生成树堆优化

#include<bits/stdc++.h>
using namespace std;
typedef pair<int, int> PII;
const int INF = 0x3f3f3f3f;
const int N1 = 5e3 + 10, N2 = 4e5 + 10;
int head[N1], nex[N2], to[N2], value[N2], cnt = 1;
int visit[N1], dis[N1], n, m, ans;
struct cmp {
    bool operator () (const PII & a, const PII & b) const {
        return a.second > b.second;
    }
};
void add(int x, int y, int w) {
    to[cnt] = y;
    value[cnt] = w;
    nex[cnt] = head[x];
    head[x] = cnt++;
}
void prime() {
    int flag = 0;
    for(int i = 1; i <= n; i++) dis[i] = INF;
    dis[1] = 0;
    priority_queue<PII, vector<PII>, cmp> q;
    q.push(make_pair(1, 0));
    while(!q.empty()) {
        int temp = q.top().first;
        int add = q.top().second;
        q.pop();
        if(visit[temp]) continue;
        visit[temp] = 1;
        flag++;
        ans += add;
        for(int i = head[temp]; i; i = nex[i]) {
            if(dis[to[i]] > value[i]) {
                dis[to[i]] = value[i];
                q.push(make_pair(to[i], value[i]));
            }
        }
    }
    if(flag == n)   printf("%d\n", ans);
    else    puts("orz");
}
int main() {
    // freopen("in.txt", "r", stdin);
    int x, y, w;
    scanf("%d %d", &n, &m);
    for(int i = 0; i < m; i++) {
        scanf("%d %d %d", &x, &y, &w);
        add(x, y, w);
        add(y, x, w);
    }
    prime();
    return 0;
}