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 <iostream>
#include <queue>
#include <utility>
#include <vector>

#define MAX_NODE 10000
#define INF 1000000000

using namespace std;

struct Edge {
	int to, w;
};
typedef pair<int, int> P;

vector<Edge> adj[MAX_NODE];
int d[MAX_NODE];

void dijkstra(int n, int start) {
	priority_queue<P, vector<P>, greater<P>> que;
	fill(d, d + n, INF);
	d[start] = 0;
	que.push({0, start});

	while (!que.empty()) {
		P p = que.top();
		que.pop();
		int v = p.second;
		if (d[v] < p.first)
			continue;
		for (int i = 0; i < adj[v].size(); i++) {
			Edge e = adj[v][i];
			if (d[e.to] > d[v] + e.w) {
				d[e.to] = d[v] + e.w;
				que.push({d[e.to], e.to});
			}
		}
	}
}

int main() {
	int n;

	cin >> n;

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

	dijkstra(n, 0);

	for (int i = 0; i < n; i++)
		cout << i << " " << d[i] << endl;

	return 0;
}

C++: #include<iostream>
#include<queue>
#include<algorithm>
#include<functional>
#define MAX 10000
#define INFTY (1<<20)
#define MPII(a,b) make_pair((a),(b))
#define PII pair<int,int>
#define FOR(i,a,b) for(int i=(a);i<(b);i++)
#define REP(i,n) for(int i=0;i<(n);i++)
using namespace std;

class Node
{
public:
	Node() {};
	int d;
	bool done;
	priority_queue<PII, vector<PII>, greater<PII>> E;
};

int main()
{
	priority_queue<PII, vector<PII>, greater<PII>> order;
	Node nodes[MAX];
	REP(i, MAX)
	{
		nodes[i].done = false;
		nodes[i].d = INFTY;
	}
	int n;
	cin >> n;
	FOR(i, 0, n)
	{
		int ID, m;
		cin >> ID >> m;
		REP(l, m)
		{
			int v, w;
			cin >> v >> w;
			PII p = MPII(w, v);
			nodes[ID].E.push(p);
		}
	}
	PII now = MPII(0, 0);
	order.push(now);
	nodes[now.second].d = 0;
	while (1)
	{
		if (!nodes[now.second].done)
		{
			while (!nodes[now.second].E.empty())
			{
				PII temp = nodes[now.second].E.top();
				nodes[now.second].E.pop();
				int nextv = temp.second;
				int w = temp.first;
				if (nodes[nextv].d > nodes[now.second].d + w)
				{
					nodes[nextv].d = nodes[now.second].d + w;
				}
				order.push(MPII(nodes[nextv].d,nextv ));
			}
			nodes[now.second].done = true;
		}
		order.pop();
		if (order.empty())break;
		now = order.top();
	}
	REP(i, n)
	{
		cout << i << " " << nodes[i].d << endl;
	}
	return 0;
}

C++: #include <bits/stdc++.h>

using namespace std;

vector<int> adja[10000], cost[10000];

#define INF (1 << 30)

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

	cin >> n;
	for (int i = 0; i < n; ++i) {
		cin >> id >> k;
		adja[id].resize(k);
		cost[id].resize(k);
		for (int j = 0; j < k; ++j) {
			cin >> adja[id][j] >> cost[id][j];
		}
	}

	priority_queue<pair<int, int>> que;
	que.push(make_pair(0, 0)); //cost, node
	int best[10000];
	fill(best, best + n, INF);
	best[0] = 0;

	while (!que.empty()) {
		pair<int, int> top = que.top();
		que.pop();

		if (best[top.second] < top.first) {
			continue;
		}

		for (int j = 0, len = adja[top.second].size(); j < len; ++j) {
			if (best[adja[top.second][j]] > top.first + cost[top.second][j]) {
				best[adja[top.second][j]] = top.first + cost[top.second][j];
				que.push(make_pair(top.first + cost[top.second][j], adja[top.second][j]));
			}
		}
	}

	for (int i = 0; i < n; ++i) {
		cout << i << " " << best[i] << endl;
	}

	return 0;
}

C++: #include <iostream>
#include <cstdio>
#include <vector>
#include <queue>
using namespace std;
const int num = 10000, num1 = 500000, INF = 20000000;
int n, d[num], c[num];
vector<pair<int, int> > v[num];
priority_queue<pair<int, int> > q;
inline void mini() {
	q.push(make_pair(0, 0));
	while (!q.empty()) {
		pair<int, int> p = q.top(); q.pop();
		int a = p.second;
		c[a] = 1;
		for (int i = 0; i < v[a].size(); i++) {
			int b = v[a][i].first;
			if (c[b] == 0 && d[b] > d[a] + v[a][i].second) {
				d[b] = d[a] + v[a][i].second;
				q.push(make_pair(d[b] * -1, b));
			}
		}
	}
		
}
int main() {
	int u, k, s, t;
	cin >> n;
	for (int i = 1; i < n; i++) {
		d[i] = INF;
		c[i] = 0;
	}
	d[0] = 0;
	for (int i = 0; i < n; i++) {
		scanf("%d%d", &u, &k);
		for (int j = 0; j < k; j++) {
			scanf("%d%d", &s, &t);
			v[u].push_back(make_pair(s, t));
		}
	}
	mini();
	for (int i = 0; i < n; i++) {
		printf("%d %d\n", i, d[i]);
	}
	return 0;
}