Go: package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

const BIG_COST = 200000

type Path struct {
	node int
	cost int
}

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

	nNodes := scanInt(sc)

	// 各頂点につながる頂点一覧を得るための隣接リスト
	graph := make([][]Path, nNodes)

	for i := 0; i < nNodes; i++ {
		u := scanInt(sc)
		k := scanInt(sc)
		graph[i] = make([]Path, k)
		for d := 0; d < k; d++ {
			graph[u][d] = Path{
				node: scanInt(sc),
				cost: scanInt(sc),
			}
		}
	}

	// 0 から各頂点への最小コストを保存する配列
	minCosts := make([]int, nNodes)

	minCosts[0] = 0
	for i := 1; i < nNodes; i++ {
		minCosts[i] = BIG_COST
	}

	// 各頂点が調査済みかどうかを保持する配列
	checked := make([]bool, nNodes)

	// 最小コストのパスを高速に取得するためのヒープ。
	// コストが小さいものほどルートに来るようにする。
	heap := NewHeap(func(a, b Path) bool {
		return a.cost < b.cost
	})

	heap.insert(Path{node: 0, cost: 0})
	for heap.size > 0 {
		u := heap.extractMax()

		// 隣接行列を使っていた時とは違い、ヒープには
		// 同じノードへのパスが複数含まれうる。そのため既によりコストの低い
		// パスが見つかっている場合は無視する。
		if minCosts[u.node] < u.cost {
			continue
		}

		checked[u.node] = true

		for _, v := range graph[u.node] {
			cost := v.cost + u.cost
			if !checked[v.node] && cost < minCosts[v.node] {
				minCosts[v.node] = cost
				heap.insert(Path{node: v.node, cost: cost})
			}
		}
	}

	w := bufio.NewWriter(os.Stdout)
	for i, cost := range minCosts {
		fmt.Fprintf(w, "%d %d\n", i, cost)
	}
	w.Flush()
}

func scanInt(sc *bufio.Scanner) int {
	sc.Scan()
	v, _ := strconv.Atoi(sc.Text())
	return v
}

// --- From ALDS1_9_C: Priority Queue

type Heap struct {
	size   int
	heap   []Path
	isHigh func(a, b Path) bool
}

func NewHeap(isHigh func(a, b Path) bool) Heap {
	heap := make([]Path, 1) // 先頭は不使用
	return Heap{size: 0, heap: heap, isHigh: isHigh}
}

func (h *Heap) insert(v Path) {
	h.size += 1
	if h.size > len(h.heap)-1 {
		h.heap = append(h.heap, v)
	} else {
		h.heap[h.size] = v
	}

	for i := h.size; i > 1; {
		parent := i / 2
		if h.isHigh(h.heap[parent], h.heap[i]) {
			break
		}
		h.heap[i], h.heap[parent] = h.heap[parent], h.heap[i]
		i = parent
	}
}

func (h *Heap) extractMax() Path {
	if h.size <= 0 {
		panic("cannot extract from empty heap")
	}

	max := h.heap[1]
	h.heap[1] = h.heap[h.size]
	h.size -= 1
	h.maxHeapify(1)

	return max
}

func (h *Heap) maxHeapify(idx int) {
	left := idx * 2
	right := left + 1
	largest := idx

	if left <= h.size {
		if h.isHigh(h.heap[left], h.heap[idx]) {
			largest = left
		}
		if right <= h.size && h.isHigh(h.heap[right], h.heap[largest]) {
			largest = right
		}
	}

	if largest != idx {
		h.heap[idx], h.heap[largest] = h.heap[largest], h.heap[idx]
		h.maxHeapify(largest)
	}
}

C++: #include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

int main()
{
	int n, u, k, v1, c1;
	const int INF = 1000000;
	
	cin >> n;
	
	vector<vector<int> > v(n), c(n);
	vector<int> w(n, INF);
	vector<bool> f(n, false);

	for (int i = 0; i < n; i++) {
		cin >> u >> k;
		for (int j = 0; j < k; j++) {
			cin >> v1 >> c1;
			v[u].push_back(v1);
			c[u].push_back(c1);
		}
	}

	w[0] = 0;

	while (true) {
		int k = -1;
		for (int i = 0; i < n; i++)
			if (!f[i] && (k == -1 || w[i] < w[k]))
				k = i;

		if (k == -1)
			break;

		f[k] = true;

		for (int i = 0; i < (int)v[k].size(); i++)
			w[v[k][i]] = min(w[v[k][i]], w[k] + c[k][i]);
	}

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

	return 0;
}

C++: #include<iostream>
#include<algorithm>
#include<queue>
using namespace std;
const int MAX = 10000;
const int INFTY = (1 << 20);
const int WHITE = 0;
const int GRAY = 1;
const int BLACK = 2;
int n;
vector<pair<int, int>> adj[MAX];
void dijkstra()
{
	priority_queue<pair<int, int>> PQ;
	int color[MAX];
	int d[MAX];
	for (int i = 0; i < n; i++)
	{
		d[i] = INFTY;
		color[i] = WHITE;
	}
	d[0] = 0;
	PQ.push(make_pair(0, 0));
	color[0] = GRAY;
	while (!PQ.empty())
	{
		pair<int, int> f = PQ.top();
		PQ.pop();
		int u = f.second;
		color[u] = BLACK;
		if (d[u] < f.first*(-1))
			continue;
		for (int j = 0; j < adj[u].size(); j++)
		{
			int v = adj[u][j].first;
			if (color[v] == BLACK)
				continue;
			if (d[v] > d[u] + adj[u][j].second)
			{
				d[v] = d[u] + adj[u][j].second;
				PQ.push(make_pair(d[v] * (-1), v));
				color[v] = GRAY;
			}
		}
	}
	for (int i = 0; i < n; i++)
		cout << i << " " << (d[i] == INFTY ? -1 : d[i]) << 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++: //Single Source Shortest Path II
#include <iostream>
#include <vector>
#include <queue>
#include <climits>

using namespace std;

static const int N = 10000;
static const int WHITE = 0;
static const int BLACK = 1;
int n, colors[N], d[N];
vector<pair<int, int> > G[N];


void dijkstra() {
    priority_queue<pair<int, int>, vector<pair<int, int> >, greater<pair<int, int> > > PQ;
    for(int i = 0; i < N; i++) {
        colors[i] = WHITE;
        d[i] = INT_MAX;
    }
    d[0] = 0;
    PQ.push(make_pair(0, 0));
    while(!PQ.empty()) {
        pair<int, int> f = PQ.top();
        PQ.pop();
        int u = f.second;
        if(colors[u] == BLACK) continue;
        for(int i = 0; i < G[u].size(); i++) {
            if(d[G[u][i].first] > f.first + G[u][i].second) {
                d[G[u][i].first] = f.first + G[u][i].second;
                PQ.push(make_pair(d[G[u][i].first], G[u][i].first));
            }

        }
    }
}

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

    dijkstra();

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

C++: #include<iostream>
#include<vector>
#include<stack>

#define INF (1 << 21)

int main() {
	int node_num;

	std::cin >> node_num;
	std::vector<std::vector<int> > node(node_num, std::vector<int>(node_num, -1));

	for (size_t i = 0; i < node.size(); i++) {
		int out, node_number;
		std::cin >> node_number >> out;
		for (int j = 0; j < out; j++) {
			int to, distance;
			std::cin >> to >> distance;
			node[node_number][to] = distance;
		}
	}

	std::vector<int> distance(node.size(), INF);
	std::stack<int> s;
	distance[0] = 0;

	s.push(0);
	while(!s.empty()) {
		int node_number = s.top(); s.pop();
		for (size_t j = 0; j < node[node_number].size(); j++) {
			if (node[node_number][j] != -1 && node[node_number][j] + distance[node_number] < distance[j]) {
				distance[j] = node[node_number][j] + distance[node_number];
				s.push(j);
			}
		}
	}

	for (size_t i = 0; i < distance.size(); i++) {
		std::cout << i << " " << distance[i] << std::endl;
	}
}

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

#define fi first
#define se second

vector<pair<int,int> >adj[10010];
priority_queue<pair<int,int> > pq;
int nodes[10010];

int main(){
	memset(nodes,-1,sizeof(nodes));
	int n,node,k,v,c;
	cin>>n;
	for (int i=0; i<n; ++i) {
		cin>>node>>k;
		for (int j=0; j<k; ++j) {
			cin>>v>>c;
			adj[node].push_back(make_pair(v,c));
		}
	}
	pq.push(make_pair(0,0));
	while(!pq.empty()){
		pair<int,int> cur=pq.top();
		pq.pop();
		if(nodes[cur.se]!=-1){//kalo udh didatengin
			continue;
		}
		else nodes[cur.se]=-cur.fi;
		for(int i=0;i<adj[cur.se].size();i++){
			pq.push(make_pair(-adj[cur.se][i].se+cur.fi,adj[cur.se][i].fi));
		}
	}
	for (int i=0; i<n; ++i) {
		cout<<i<<" "<<nodes[i]<<endl;
	}
	return 0;
}