Go: package main

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

// I/O
type Scanner struct {
	sc *bufio.Scanner
}

func NewScanner() *Scanner {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	sc.Buffer(make([]byte, 1024), int(1e+9))
	return &Scanner{sc}
}

func (s *Scanner) nextStr() string {
	s.sc.Scan()
	return s.sc.Text()
}

func (s *Scanner) nextInt() int {
	i, e := strconv.Atoi(s.nextStr())
	if e != nil {
		panic(e)
	}
	return i
}

func (s *Scanner) nextFloat() float64 {
	f, e := strconv.ParseFloat(s.nextStr(), 64)
	if e != nil {
		panic(e)
	}
	return f
}

func (s *Scanner) nextRuneSlice() []rune {
	return []rune(s.nextStr())
}

func (s *Scanner) nextIntSlice(n int) []int {
	res := make([]int, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextInt()
	}
	return res
}

func (s *Scanner) nextFloatSlice(n int) []float64 {
	res := make([]float64, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextFloat()
	}
	return res
}

// Arithmetic
func max(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m < i {
			m = i
		}
	}
	return m
}

func min(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m > i {
			m = i
		}
	}
	return m
}

func abs(x int) int {
	if x > 0 {
		return x
	}
	return -x
}

func pow(x, y int) int {
	res := 1
	for i := 0; i < y; i++ {
		res *= x
	}
	return res
}

func ceil(a, b int) int {
	if a%b == 0 {
		return a / b
	} else {
		return a/b + 1
	}
}

// Sort
type RuneSlice []rune

func (a RuneSlice) Len() int           { return len(a) }
func (a RuneSlice) Less(i, j int) bool { return a[i] < a[j] }
func (a RuneSlice) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }

// Main
const INF = 1 << 60

type Edge struct {
	to, cost int
}

type Node struct {
	id, cost int
}

type PQ []Node

func (pq PQ) Len() int           { return len(pq) }
func (pq PQ) Less(i, j int) bool { return pq[i].cost < pq[j].cost }
func (pq PQ) Swap(i, j int)      { pq[i], pq[j] = pq[j], pq[i] }

func (pq *PQ) Push(x interface{}) {
	*pq = append(*pq, x.(Node))
}

func (pq *PQ) Pop() interface{} {
	old := *pq
	n := len(old)
	x := old[n-1]
	*pq = old[0 : n-1]
	return x
}

func main() {
	sc := NewScanner()
	wtr := bufio.NewWriter(os.Stdout)
	N := sc.nextInt()
	E := make([][]Edge, N)
	for i := 0; i < N; i++ {
		id, k := sc.nextInt(), sc.nextInt()
		E[id] = make([]Edge, k)
		for j := 0; j < k; j++ {
			to, cost := sc.nextInt(), sc.nextInt()
			E[id][j] = Edge{to, cost}
		}
	}

	d := make([]int, N)
	for i := 0; i < N; i++ {
		d[i] = INF
	}
	done := make([]bool, N)
	pq := &PQ{}
	heap.Init(pq)
	d[0] = 0
	heap.Push(pq, Node{0, 0})
	for pq.Len() > 0 {
		cur := heap.Pop(pq).(Node).id
		if done[cur] {
			continue
		}
		done[cur] = true
		for i := 0; i < len(E[cur]); i++ {
			to, cost := E[cur][i].to, E[cur][i].cost+d[cur]
			if !done[to] && cost < d[to] {
				d[to] = cost
				heap.Push(pq, Node{to, cost})
			}
		}
	}

	for i := 0; i < N; i++ {
		fmt.Fprintln(wtr, i, d[i])
	}
	wtr.Flush()
}

C++: #include <iostream>
#include <cmath>
#include <vector>
#include <set>
#include <string>
#include <algorithm>

constexpr int INF = 10000001;

int main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(0);
    int n, u, k, vv, cc;
    std::cin >> n;
    std::vector<std::vector<int>> v(n), c(n);
    std::vector<int> d(n), p(n);
    std::set<int> v_s, s;
    for (int i=0; i<n; i++) {
        std::cin >> u >> k;
        for (int j=0; j<k; j++) {
            std::cin >> vv >> cc;
            v[u].push_back(vv);
            c[u].push_back(cc);
        }
        d[i] = INF;
        v_s.insert(i);
    }
    d[0] = 0;
    //v_s.erase(0);

    while (not v_s.empty()) {
        int mind=INF+1;
        int minnode;
        auto iter = v_s.begin();
        for (int i=0; i<v_s.size(); i++,iter++) {
            if (d[*iter] < mind) {
                mind = d[*iter];
                minnode = *iter;
            }
        }
        v_s.erase(minnode);
        s.insert(minnode);
        for (int i=0; i<v[minnode].size(); i++) {
            if (v_s.find(v[minnode][i]) != v_s.end() and mind + c[minnode][i] < d[v[minnode][i]]) {
                d[v[minnode][i]] = mind + c[minnode][i];
                p[v[minnode][i]] = minnode;
            }
        }
    }

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

    return 0;
}

C++: ///
// File:  alds1_12_c.cpp
// Author: ymiyamoto
//
// Created on Wed Oct 18 22:36:29 2017
//

#include <cstdint>
#include <iostream>
#include <queue>
#include <vector>

using namespace std;

#define SIZE 10000

struct route_t {
  uint32_t node;
  int64_t weight;

  bool operator<(const route_t &r) const
  {
    return weight > r.weight;
  }
};

static vector<route_t> graph[SIZE];
static int64_t costs[SIZE];
static bool visited[SIZE];
static priority_queue<route_t> q;

static void dikstra()
{
  q.push({0, 0});
  costs[0] = 0;

  while (!q.empty()) {
    route_t r = q.top();
    q.pop();

    if (!visited[r.node]) {
      visited[r.node] = true;
      for (uint32_t i = 0; i < graph[r.node].size(); i++) {
        int64_t cost = graph[r.node][i].weight;
        uint32_t node = graph[r.node][i].node;
        if (cost != -1) {
          if (costs[r.node] + cost < costs[node]) {
            costs[node] = costs[r.node] + cost;
          }
          q.push({node, cost});
        }
      }
    }
  }
}

int32_t main()
{
  uint32_t n;
  cin >> n;

  for (uint32_t i = 0; i < n; i++) {
    costs[i] = INT32_MAX;
  }

  for (uint32_t i = 0; i < n; i++) {
    uint32_t id, k;
    cin >> id >> k;
    for (uint32_t j = 0; j < k; j++) {
      route_t r;
      cin >> r.node >> r.weight;
      graph[id].push_back(r);
    }
  }

  dikstra();

  for (uint32_t i = 0; i < n; i++) {
    cout << i << " " << costs[i] << endl;
  }

  return 0;
}

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

const int NMAX = 10000;
const int AMAX = 9999999;

const int BLACK = 2;
const int GRAY = 1;
const int WHITE = 0;

vector<pair<int, int> > A[NMAX];
int c[NMAX];
int d[NMAX];
int n;

void dijkstra(int s) {
	for (int i = 0; i < n; i++) {
		c[i] = WHITE;
		d[i] = AMAX;
	}

	d[s] = 0;
	c[s] = GRAY;
	priority_queue<pair<int, int> > PQ;
	PQ.push(make_pair(d[s], s));

	while (!PQ.empty()) {
		pair<int, int> f = PQ.top(); PQ.pop();
		int minw, u;
		minw = f.first;
		u = f.second;

		c[u] = BLACK;

		if (d[u] < minw * (-1)) continue;

		for (int i = 0; i < A[u].size(); i++) {
			int v = A[u][i].first;
			int w = A[u][i].second;
			if (c[v] == BLACK) continue;

			if (d[v] > d[u] + w) {
				d[v] = d[u] + w;
				PQ.push(make_pair(d[v] * (-1), v));
				c[v] = GRAY;
			}
		}
	}
}

int main() {
	scanf("%d", &n);

	for (int i = 0; i < n; i++) {
		int u, k;
		scanf("%d %d", &u, &k);

		for (int j = 0; j < k; j++) {
			int v, c;
			scanf("%d %d", &v, &c);
			A[u].push_back(make_pair(v, c));
		}
	}

	dijkstra(0);

	for (int i = 0; i < n; i++) {
		printf("%d %d\n", i, d[i]);
	}

	return 0;
}