Go: package main

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

var scanner = bufio.NewScanner(os.Stdin)

func nextString() string {
	scanner.Scan()
	return scanner.Text()
}

func nextInt() int {
	n, err := strconv.Atoi(nextString())
	if err != nil {
		fmt.Printf("strconv.Atoi failed: %v\n", err)
	}
	return n
}

var infty = 1000000000

type DirectedGraphNodeID int

type DirectedGraphNode struct {
	key         DirectedGraphNodeID
	adjacents   []*DirectedGraphNode
	costs       []int
	distance    int
	predecessor *DirectedGraphNode
}

func newDirectedGraph(nNodes int) *DirectedGraph {
	graph := DirectedGraph{}
	graph.nodes = make([]*DirectedGraphNode, nNodes)
	for i := 0; i < nNodes; i++ {
		node := DirectedGraphNode{}
		node.key = DirectedGraphNodeID(i)
		node.distance = infty
		graph.nodes[i] = &node
	}
	return &graph
}

type DirectedGraph struct {
	nodes []*DirectedGraphNode
}

func (g *DirectedGraph) setAdjacency(i, j DirectedGraphNodeID, cost int) {
	g.nodes[i].adjacents = append(g.nodes[i].adjacents, g.nodes[j])
	g.nodes[i].costs = append(g.nodes[i].costs, cost)
}

func (g *DirectedGraph) print() {
	for i := 0; i < len(g.nodes); i++ {
		node := g.nodes[i]
		key := node.key
		strings := []string{strconv.Itoa(int(key)), strconv.Itoa(node.distance)}
		for j := 0; j < len(node.adjacents); j++ {
			nodeJ := fmt.Sprintf("(%v, %v)", node.adjacents[j].key, node.costs[j])
			strings = append(strings, nodeJ)
		}
		fmt.Printf("%v\n", strings)
	}
}

func (g *DirectedGraph) relaxEdge(l, r *DirectedGraphNode, w int) {
	if r.distance > l.distance+w {
		// fmt.Printf("%v -> %v, %v\n", l.key, r.key, l.distance+w)
		r.distance = l.distance + w
		r.predecessor = l
	}
}

func main() {
	scanner.Split(bufio.ScanWords)

	nNodes := nextInt()
	graph := newDirectedGraph(nNodes)

	for i := 0; i < nNodes; i++ {
		iNode := DirectedGraphNodeID(nextInt())
		nAdjacent := nextInt()
		for j := 0; j < nAdjacent; j++ {
			jNode := DirectedGraphNodeID(nextInt())
			cost := nextInt()
			graph.setAdjacency(iNode, jNode, cost)
		}
	}

	graph.nodes[0].distance = 0
	for iNode := 0; iNode < nNodes; iNode++ {
		for iLeft := 0; iLeft < len(graph.nodes); iLeft++ {
			nodeLeft := graph.nodes[iLeft]
			for iRight := 0; iRight < len(nodeLeft.adjacents); iRight++ {
				nodeRight := nodeLeft.adjacents[iRight]
				cost := nodeLeft.costs[iRight]
				graph.relaxEdge(nodeLeft, nodeRight, cost)
			}
		}
	}

	// graph.print()

	for iNode := 0; iNode < len(graph.nodes); iNode++ {
		node := graph.nodes[iNode]
		fmt.Println(node.key, node.distance)
	}
}

C++: #include <algorithm>
#include <iostream>
#include <string>
using namespace std;
static const int NMAX = 100;
#define INF (1 << 30)
int ADJ[NMAX][NMAX];

int main() {
  int n;
  cin >> n;
  for (int i = 0; i < n; i++)
    for (int j = 0; j < n; j++)
      ADJ[i][j] = INF;

  for (int i = 0; i < n; i++) {
    int id, nn;
    cin >> id  >> nn;
    for (int j = 0; j < nn; j++) {
      int to, weight;
      cin >> to >> weight;
      ADJ[id][to] = weight;
    }
  }

  bool visited[n];
  int dist[n];

  // add node 0
  for (int i = 0; i < n; i++) {
    dist[i] = ADJ[0][i];
    visited[i] = false;
  }
  visited[0] = true;
  dist[0] = 0;

  while (true) {
    int minnode = -1;
    int mincost = INF;
    // find nearest node
    for (int i = 0; i < n; i++) {
      if (visited[i] == false && dist[i] < mincost) {
        minnode = i;
        mincost = dist[i];
      }
    }
    if (minnode == -1)
      break;

    // add node
    visited[minnode] = true;

    // update dist
    for (int i = 0; i < n; i++) {
      if (visited[i] == false)
        dist[i] = min(dist[i], dist[minnode] + ADJ[minnode][i]);
    }
  }

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

C++: a

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

static const int MAX = 100;
static const int INFTY = (1<<21);
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

int n,M[MAX][MAX];

void dijkstra(){
    int minv;
    int d[MAX],color[MAX];
    
    for(int i=0; i<n; i++){
        d[i] = INFTY;
        color[i] = WHITE;
    }
    
    d[0] = 0;
    //color[0] = GRAY;
    while (1) {
        minv = INFTY;
        int u = -1;
        for(int i=0; i<n; i++){
            if(minv > d[i] && color[i] != BLACK){
                u = i;
                minv = d[i];
            }
        }
        if(u==-1) break;
        color[u] = BLACK;
        for(int v=0; v<n; v++){
            if(color[v]!=BLACK && M[u][v]!=INFTY){
                if(d[v] > d[u] + M[u][v]){
                    d[v] = d[u]+M[u][v];
                    color[v] = GRAY;
                }
            }
        }
    }
    for(int i=0; i<n; i++){
        cout << i << " " << (d[i]==INFTY ? -1 : d[i]) << endl;
    }
}

int main(){
    cin >> n;
    for(int i=0; i<n; i++){
        for(int j=0; j<n; j++){
            M[i][j] = INFTY;
        }
    }
    
    int k,c,u,v;
    for(int i=0; i<n; i++){
        cin >> u >> k;
        for(int j=0; j<k; j++){
            cin >> v >> c;
            M[u][v] = c;
        }
    }
    
    dijkstra();
}

C++: #include <iostream>
#include <algorithm>
#define N 100
#define INF (1<<30)
using namespace std;

int n, M[N][N], d[N], color[N] = {0};

void Dijk(int s) {
	int min;
	for (int i = 0;i < n;i++) d[i] = INF;
	d[s] = 0;
	color[s] = 1;
	while (true) {
		int u=-1;
	    min = INF;
		for (int i = 0;i < n;i++) {
			if (color[i] != 2 && d[i] < min)
			{
				u = i;
				min = d[u];
			}
		}

		if (u==-1) break;

		color[u] = 2;

		for (int v = 0;v < n;v++) {
			if (color[v] != 2 && M[u][v] != INF)
				if (d[v] > d[u] + M[u][v]) {
					d[v] = d[u] + M[u][v];
					color[v] = 1;
				}
		}
	}

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

}

int main() {

	for (int i = 0;i < N;i++)
		for (int j = 0;j < N;j++) M[i][j] = INF;

	cin >> n;
	int u, v, k;
	for (int i = 0;i < n;i++) {
		cin >> u;
		cin >> k;
		for (int j = 0;j < k;j++) {
			cin >> v;
			cin >> M[u][v];
		}
	}

	Dijk(0);

}

C++: ///
// File:  alds1_12_b.cpp
// Author: ymiyamoto
//
// Created on Wed Oct 18 21:59:56 2017
//

#include <cstdint>
#include <iostream>

using namespace std;
#define SIZE 100
static int64_t graph[SIZE][SIZE];
static int64_t costs[SIZE];
static bool visited[SIZE];

static void dikstra(uint32_t n)
{
  costs[0] = 0;

  while (true) {
    int32_t min_index = -1;
    int64_t min_cost = INT32_MAX;

    for (uint32_t i = 0; i < n; i++) {
      if (!visited[i] && costs[i] < min_cost) {
        min_cost = costs[i];
        min_index = i;
      }
    }

    if (min_index == -1) break;

    visited[min_index] = true;

    for (uint32_t i = 0; i < n; i++) {
      if (graph[min_index][i] != -1) {
        if (costs[min_index] + graph[min_index][i] < costs[i]) {
          costs[i] = costs[min_index] + graph[min_index][i];
        }
      }
    }
  }
}

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

  for (uint32_t i = 0; i < n; i++) {
    for (uint32_t j = 0; j < n; j++) {
      graph[i][j] = -1;
    }
    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++) {
      int64_t v, c;
      cin >> v >> c;
      graph[id][v] = c;
    }
  }

  dikstra(n);

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

  return 0;
}