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 <iostream>
using namespace std;
#define MAX 100
#define INFTY 10000001
#define WHITE 0
#define GRAY 1
#define BLACK 2
#define DEFLT 0 // 初期値

int M[MAX][MAX], d[MAX];

void dijkstra(int n){
  int mincost, u, color[n], p[n];
  for(int i=0; i<n; i++){
    color[i] = WHITE;
    d[i] = INFTY;
  }

  d[DEFLT] = 0;
  p[DEFLT] = -1;

  while(true){
    mincost = INFTY;
    for(int i=0; i<n; i++){
      if(color[i] != BLACK && d[i] < mincost){
        mincost = d[i];
        u = i;
      }
    }

    if(mincost == INFTY) break;

    color[u] = BLACK;

    for(int v=0; v<n; v++){
      if(color[v] != BLACK && M[u][v] < INFTY){
        if(d[u] + M[u][v] < d[v]){
          d[v] = d[u] + M[u][v];
          p[v] = u;
          color[v] = GRAY;
        }
      }
    }
  }
}

int main(void){
  int n, u, k, v, c;
  cin >> n;

  for(u=0; u<MAX; u++){
    for(v=0; v<MAX; v++){
      M[u][v] = INFTY;
    }
  }

  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(n);

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

C++: #include<bits/stdc++.h>
#include<string>
#include<cctype>
#include<cmath>
#include<queue>
#include<stack> 
#define rep(i,n) for(int i=0;i<(n);i++)
using namespace std;
const int MAX_V=105;
int INF = 1000000000;
struct edge{int to,cost;};
typedef pair <int,int> P;

int V;
vector <edge> G[MAX_V];
int d[MAX_V];

void dijkstra(int s){
  priority_queue<P,vector<P>,greater<P> > que;
  fill(d,d+V,INF);
  d[s]=0;
  que.push(P(0,s));
  
  while(!que.empty()){
    P p = que.top(); que.pop();
    int v= p.second;
    if(d[v]<p.first)continue;
    for(int i=0 ;i<G[v].size();i++){
      edge e =G[v][i];
      if(d[e.to]>d[v]+e.cost){
        d[e.to] = d[v] + e.cost;
        que.push(P(d[e.to],e.to));
      }
    }
  }
} 
  
int main(){
  int n;
  cin >> n; V=n;
  rep(i,n){
    int u,k;
    cin >> u >> k;
    rep(j,k){
      int to,cost;
      cin >> to >> cost;
      G[u].push_back(edge{to,cost});
    }
  }     

  dijkstra(0);
  rep(i,n){
    cout << i << ' ' << d[i] << endl;
  }
  return 0;
}

C++: #include <iostream>
#include <queue>
#define INF 1000000000
using namespace std;

struct edge{ int to,cost; };
typedef pair<int,int> P;

int main(){
	int n;
	vector<edge> es[100];
	priority_queue<P,vector<P>,greater<P> > que;
	int d[100];
	cin >> n;
	for(int i = 0;i < n;i++){
		int now,m;
		cin >> now >> m;
		for(int j = 0;j < m;j++){
			int a,b;
			cin >> a >> b;
			es[now].push_back({a,b});
		}
		d[i] = INF;
	}
	d[0] = 0;
	que.push(make_pair(0,0));
	while(!que.empty()){
		P p = que.top();
		que.pop();
		int v = p.second;
		if(d[v] < p.first) continue;
		for(int i = 0;i < es[v].size();i++){
			edge e = es[v][i];
			if(d[e.to] > d[v] + e.cost){
				d[e.to] = d[v] + e.cost;
				que.push(make_pair(d[e.to],e.to));
			}
		}
	}
	for(int i = 0;i < n;i++) cout << i << " " << d[i] << endl;
	return 0;
}

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];

int 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();

  return 0;
}