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 <map>
#include <queue>
#include <algorithm>
#define INF 1<<30
using namespace std;
int main() {
	cin.tie(0);ios::sync_with_stdio(false);
	int V; cin >> V;
	vector<vector<pair<int, int>>> g(V);
	vector<int> dp(V);
	queue<int> q;

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

	//initialize
	fill(dp.begin(), dp.end(), INF);
	dp[0] = 0;
	q.push(0);

	//Dijkstra
	while (!q.empty()) {
		int k = q.front(); q.pop();
		for (int i = 0; i < g[k].size();i++) {
			int next = g[k][i].first;
			int w = g[k][i].second;
			if (dp[k] + w < dp[next]) {
				dp[next] = dp[k] + w;
				q.push(next);
			}
		}
	}

	//output
	for (int i = 0; i < V;i++) {
		cout << i << " " << dp[i] << endl;
	}
}

C++: #include <algorithm>
#include <iostream>
#include <list>
#include <vector>

class TNode
{
	std::list<std::pair<TNode*, int> > FNexts;
	int  FDistance;
public:
	TNode()
	: FDistance(-1)
	{
	}
	
	int GetDistance()const {return FDistance;}
	
	void Push(TNode* New, int Weight)
	{
		FNexts.push_back(std::make_pair(New, Weight));
	}
	
	void Visit(int Distance)
	{
		if(FDistance >= 0 && Distance > FDistance) return;
		FDistance = Distance;
		for(std::list<std::pair<TNode*, int> >::iterator It = FNexts.begin(); It != FNexts.end(); ++It){
			It->first->Visit(Distance + It->second);
		}
	}
};

class TGraph
{
	std::vector<TNode*> FNodes;
public:
	TGraph(int Count)
	: FNodes(Count)
	{
		for(int i = 0; i < Count; ++i){
			FNodes[i] = new TNode();
		}
	}
	
	~TGraph()
	{
		for(unsigned int i = 0; i < FNodes.size(); ++i){
			delete FNodes[i];
		}
	}
	
	void InputNode()
	{
		int Index;
		std::cin >> Index;
		int BranchCount;
		std::cin >> BranchCount;
		for(int i = 0; i < BranchCount; ++i){
			int Target, Weight;
			std::cin >> Target >> Weight;
			FNodes[Index]->Push(FNodes[Target], Weight);
		}
	}
	
	void BreathFirstSearch()
	{
		FNodes[0]->Visit(0);
	}
	
	int Distance(int Target)const
	{
		return FNodes[Target]->GetDistance();
	}
};

int main()
{
	int Count;
	std::cin >> Count;
	TGraph Graph(Count);
	for(int i = 0; i < Count; ++i){
		Graph.InputNode();
	}
	Graph.BreathFirstSearch();
	
	for(int i = 0; i < Count; ++i){
		std::cout << i << " " << Graph.Distance(i) << std::endl;
	}
	return 0;
}

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

#define INF (INT64_MAX/2)
typedef pair<long long, int> P;

int main()
{
	int n;
	cin >> n;
	vector<vector<P>> g( n );
	for( int i = 0; i < n; i++ ) {
		int u, k;
		cin >> u >> k;
		g[u].resize( k );
		for( int j = 0; j < k; j++ ) {
			int v, c;
			cin >> v >> c;
			g[u][j] = P( c, v );
		}
	}

	vector<long long> d( n, INF );
	d[0] = 0;
	priority_queue<P, vector<P>, greater<P>> que;
	que.push( P( 0, 0 ) );
	while( !que.empty() ) {
		P p = que.top();
		que.pop();
		int c = p.first;
		int u = p.second;
		for( P e : g[u] ) {
			int cost = e.first;
			int v = e.second;
			if( d[v] <= d[u] + cost ) continue;
			d[v] = d[u] + cost;
			que.push( e );
		}
	}

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

C++: //Single Source Shortest Path II
#include <iostream>
#include <vector>
#include <climits>

using namespace std;

static const int N = 100;
static const int WHITE = 0;
static const int BLACK = 1;
int n, colors[N], d[N];
vector<pair<int, int> > G[N];

void dijkstra() {
    int u, mind;
    for(int i = 0; i < N; i++) {
        colors[i] = WHITE;
        d[i] = INT_MAX;
    }
    d[0] = 0;
    while(1) {
        u = -1;
        mind = INT_MAX;
        for(int i = 0; i < n; i++) {
            if(colors[i] == WHITE && d[i] < mind) {
                u = i;
                mind = d[i];
            }
        }
        if(u == -1) break;
        colors[u] = BLACK;
        for(int i = 0; i < G[u].size(); i++) {
            d[G[u][i].first] = min(d[G[u][i].first], mind + G[u][i].second);
        }
    }
}

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;
    }
}