Go: package main

import (
	"bufio"
	"container/heap"
	"fmt"
	"os"
	"strconv"
)

//make priority queue
type Item struct {
	id       int
	priority int // this state is priority and distans from start
	index    int
}

type PriorityQueue []*Item

func (pq PriorityQueue) Len() int { return len(pq) }

// we want the ascending-priority-queue.
// So we use less than here.
func (pq PriorityQueue) Less(i, j int) bool {
	return pq[i].priority < pq[j].priority
}

func (pq PriorityQueue) Swap(i, j int) {
	pq[i], pq[j] = pq[j], pq[i]
	pq[i].index = j
	pq[j].index = i
}

func (pq *PriorityQueue) Push(x interface{}) {
	n := len(*pq)
	item := x.(*Item)
	item.index = n
	*pq = append(*pq, item)
}

func (pq *PriorityQueue) Pop() interface{} {
	old := *pq
	n := len(old)
	item := old[n-1]
	item.index = -1 //for safety
	*pq = old[0 : n-1]
	return item
}

func (pq *PriorityQueue) update(dist int, id int) {
	for _, i := range *pq {
		if i.id == id {
			if i.priority > dist {
				i.priority = dist
			}
		}
	}
}

// the main code
func nextInt(sc *bufio.Scanner) int {
	sc.Scan()
	n, _ := strconv.Atoi(sc.Text())
	return n
}

func dikstra(dist [][]int, n int) []int {
	// preparate priority queue
	inf := 1 << 30
	pq := make(PriorityQueue, n)
	shortests := make([]int, n)
	for i := 0; i < n; i++ {
		pq[i] = &Item{
			id:       i,
			priority: inf,
			index:    i,
		}

		shortests[i] = inf
	}
	pq[0].priority = 0
	shortests[0] = 0
	heap.Init(&pq)

	for pq.Len() > 0 {
		item := heap.Pop(&pq).(*Item)
		shortests[item.id] = item.priority
		for id, d := range dist[item.id] {
			if d != -1 {
				pq.update(item.priority+d, id)
			}
		}
		heap.Init(&pq)
	}
	return shortests
}

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)

	// init
	n := nextInt(sc)
	dist := make([][]int, n)
	for i := 0; i < n; i++ {
		dist[i] = make([]int, n)
		for j := 0; j < n; j++ {
			dist[i][j] = -1
		}
	}

	// std Input
	for i := 0; i < n; i++ {
		u := nextInt(sc)
		k := nextInt(sc)
		for j := 0; j < k; j++ {
			v, c := nextInt(sc), nextInt(sc)
			dist[u][v] = c
		}
	}

	shortests := dikstra(dist, n)
	for i, d := range shortests {
		fmt.Printf("%d %d\n", i, d)
	}
}

C++: #include <cmath>
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <climits>
#include <map>
#include <list>
#include <stack>
#include <queue>
#include <vector>
#include <string>
#include <sstream>
#include <fstream>
#include <iostream>
#include <algorithm>
using namespace std;

int *c;

struct job {
	int id;
	job(int i){
		this->id = i;
	}
	bool operator<(job j) const {
		return c[this->id] > c[j.id];
	}
};

int main() {
	int n;
	scanf("%d", &n);
	
	c = new int[n];
	vector<vector<pair<int, int> > > paths;
	
	for(int i = 0; i < n; i++){
		int u, k;
		scanf("%d %d", &u, &k);
		
		vector<pair<int, int> > path;
		c[u] = u ? INT_MAX : 0;
		while(k--){
			int v, c;
			scanf("%d %d", &v, &c);
			path.push_back(make_pair(v, c));
		}
		paths.push_back(path);
	}
	
	priority_queue<job> q;
	q.push(job(0));
	while(q.size()){
		int i = q.top().id;
		q.pop();
		
		for(int j = 0; j < paths[i].size(); j++){
			int dest = paths[i][j].first;
			int cost = paths[i][j].second;
			if(c[dest] > c[i] + cost){
				c[dest] = c[i] + cost;
				q.push(job(dest));
			}
		}
	}
	
	for(int i = 0; i < n; i++){
		printf("%d %d\n", i, c[i]);
	}
}

C++: #include <iostream>
#include <vector>
#include <queue>
using namespace std;
typedef long long ll;
typedef pair<ll, ll> Pair;
ll inf = 1e10;
int MAX_V;

ll V, E;
vector<Pair> G[100010];
ll d[100010];

void dijkstra(ll s) {
    priority_queue<Pair, vector<Pair>, greater<Pair>> que;
    fill(d, d + V, inf);
    d[s] = 0;
    que.push(Pair(0, s));
    
    while (!que.empty()) {
        Pair p = que.top();
        que.pop();
        
        ll v = p.second;
        if (d[v] < p.first) continue;
        for (int i = 0; i < G[v].size(); i++) {
            Pair e = G[v][i];
            if (d[e.first] > d[v] + e.second) {
                d[e.first] = d[v] + e.second;
                que.push(Pair(d[e.first], e.first));
            }
        }
    }
}

int main() {
    cin >> V;
    for (int i = 0; i < V; i++) {
        int a, et;
        cin >> a >> et;
        for (int j = 0; j < et; j++) {
            int b;
            ll r;
            cin >> b >> r;
            G[a].emplace_back(b, r);
            //G[b].emplace_back(a, r);
        }
    }

    dijkstra(0);
    for (int i = 0; i < V; i++) {
        cout << i << " " << d[i] << endl;
    }

}

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

static const int N = 10001;
static const int INF = (1 << 30);
static const int WHITE = 0;
static const int GRAY  = 1;
static const int BLACK = 2;

int n;
vector<pair<int ,int> > adj[N];

void dijkstra(){
    priority_queue<pair<int,int> > p_q;
    int color[N];
    int d[N];
    for(int i=0;i<n;i++){
        d[i] = INF;
        color[i] = GRAY;
    }

    d[0] = 0;
    p_q.push(make_pair(0,0));
    color[0] = GRAY;

    while(!p_q.empty()){
        pair<int,int> f = p_q.top();
        p_q.pop();
        int u = f.second;
        color[u] = BLACK;

        if(d[u] < f.first*-1) continue;

        for(int i=0;i<adj[u].size();i++){
            int v = adj[u][i].first;
            if(color[v] == BLACK) continue;
            if(d[v] > d[u]+adj[u][i].second){
                d[v] = d[u]+adj[u][i].second;
                p_q.push(make_pair(d[v]*-1,v));
                color[v] = GRAY;
            }
        }
    }

    for(int i=0;i<n;i++){
        cout << i << ' ';
        if(d[i] == INF)
            cout << -1;
        else 
            cout << d[i];
        cout << endl;
    }
}

int main(){
    int k,u,v,c;

    cin >> n;
    for(int i=0;i<n;i++){
        cin >> u >> k;
        for(int j=0;j<k;j++){
            cin >> v >> c;
            adj[u].push_back(make_pair(v,c));
        }
    }

    dijkstra();
}

C++: #include <iostream>
#include <limits.h>
#include <vector>
#include <queue>

using namespace std;

struct Node {
    int id;
    int cost;
    bool done;
    vector<int> next_node;
    vector<int> len_cost;

    bool operator<(const Node& right) const {
        return cost > right.cost;
    }
} node[10000];

int main() {
    int n, id, k;

    cin >> n;
    for (int i = 0; i < n; i++) {
        cin >> id >> k;
        node[id].id = id;
        node[id].cost = INT_MAX;
        node[id].done = false;
        node[id].next_node.resize(k);
        node[id].len_cost.resize(k);
        for (int j = 0; j < k; j++) {
            cin >> node[id].next_node[j] >> node[id].len_cost[j];
        }
    }

    priority_queue<Node> q;
    node[0].cost = 0;
    q.push(node[0]);
    while (!q.empty()) {
        Node temp = q.top();
        q.pop();

        if (temp.done == true) {
            continue;
        }
        node[temp.id].done = true;

        for (int i = 0; i < temp.next_node.size(); i++) {
            int to = temp.next_node[i];
            int cost = temp.cost + temp.len_cost[i];
            if (node[to].cost > cost) {
                node[to].cost = cost;
                q.push(node[to]);
            }
        }
    }

    for (int i = 0; i < n; i++) {
        cout << i << " " << node[i].cost << endl;
    }
    
    return 0;
}