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 <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)

static const int MAX = 10000;
static const int INFTY = (1<<20);
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

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

// int prim() {
//    int u, minv;
//    int d[MAX], p[MAX], color[MAX];

//    // 初期化
//    rep(i, n) {
//       d[i] = INFTY;
//       p[i] = -1;
//       color[i] = WHITE;
//    }

//    d[0] = 0;

//    while(1) {
//       minv = INFTY;
//       u = -1;

//       rep(i, n){
//          if (minv > d[i] && color[i] != BLACK) {
//             u = i;
//             minv = d[i];
//          }
//       }
//       if(u == -1) break;
//       // uの決定
//       color[u] = BLACK;

//       rep(v, n) {
//          if(color[v] != BLACK && M[u][v] != INFTY) {
//             if(d[v] > M[u][v]) {
//                d[v] = M[u][v];
//                p[v] = u;
//                color[v] = GRAY;
//             }
//          }
//       }
//    }
//    int sum = 0;
//    rep(i, n) {
//       if(p[i] != -1) sum += M[i][p[i]];
//    }
//    return sum;
// }

// void dijkstra() {
//    int minv;
//    int d[MAX], color[MAX];

//    // 初期化
//    rep(i, n) {
//       d[i] = INFTY;
//       color[i] = WHITE;
//    }

//    d[0] = 0;
//    color[0] = GRAY;

//    while(true) {
//       minv = INFTY;
//       int u = -1;
//       rep(i, n) {
//          if(minv > d[i] && color[i] != BLACK) {
//             u = i;
//             minv = d[i];
//          }
//       }
//       if (u == -1) break;

//       // 最も小さいコストのuが決まる 初回は必ず0になる
//       color[u] = BLACK;

//       rep(v, n) {
//          // 0 ~ n-1の頂点が未訪問かつuとの経路がある場合
//          if(color[v] != BLACK && M[u][v] != INFTY) {
//             // 頂点uを通った方が目的地に近い場合
//             if (d[v] > d[u] + M[u][v]) {
//                d[v] = d[u] + M[u][v];
//                color[v] = GRAY;
//             }
//          }
//       }
//    }

//    rep(i, n) {
//       cout << i << " " << (d[i] == INFTY ? -1 : d[i]) << endl;
//    }
// }

void dijkstra() {
   priority_queue< pair<int, int> > PQ;
   int color[MAX];
   int d[MAX];

   rep(i, n) {
      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;

      rep(j, adj[u].size()) {
         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;
         }
      }
   }
   rep(i, n) {
      cout << i << " " << (d[i] == INFTY ? -1 : d[i]) << endl;
   }
}


int main(){
   cin >> n;
   int k, c, u, v;
   rep(i, n) {
      cin >> u >> k;
      rep(j, k){
         // v は頂点 cはコスト
         cin >> v >> c;
         adj[u].push_back(make_pair(v, c));
      }
   }

   dijkstra();

   return 0;
}

C++: 
import java.io.IOException;
import java.util.Arrays;
import java.util.HashSet;
import java.util.Scanner;
import java.util.Set;

public class Main {

	public static void main(String[] args) throws IOException {

		Scanner in = new Scanner(System.in);

		int u = in.nextInt();
		int[][] mat = new int[u][u];
		for (int i = 0; i < u; i++) {
			Arrays.fill(mat[i], -1);
		}
		for (int i = 0; i < u; i++) {
			int fromNode = in.nextInt();
			int toNodeCount = in.nextInt();
			for (int j = 0; j < toNodeCount; j++) {
				int toNode = in.nextInt();
				int edgeWeight = in.nextInt();
				mat[fromNode][toNode] = edgeWeight;
			}
		}

		// solve
		Set<Integer> x = new HashSet<>();
		Set<Integer> y = new HashSet<>();
		boolean[] visit = new boolean[u];
		for (int i = 1; i < u; i++) {
			y.add(i);
		}
		int[] nodeCost = new int[u];
		Arrays.fill(nodeCost, Integer.MAX_VALUE);
		x.add(0);
		nodeCost[0] = 0;
		visit[0] = true;

		while (!y.isEmpty()) {
			int min = Integer.MAX_VALUE;
			int v = -1;
			for (int from : x) {
				for (int to = 0; to < u; to++) {
					int visitCost = mat[from][to] + nodeCost[from];
					// toのノードが最小コストで訪問済でない場合
					if (mat[from][to] != -1 && !visit[to] && visitCost <= nodeCost[to]) {
						nodeCost[to] = visitCost;
						if (nodeCost[to] < min) {
							min = nodeCost[to];
							v = to;
						}
					}
				}
			}
			x.add(v);
			y.remove(v);
			visit[v] = true;
		}

		for (int i = 0; i < u; i++) {
			System.out.println(i + " " + nodeCost[i]);
		}
	}

}