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;
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; // スタート位置はノード0
    color[0] = GRAY;

    while(1){
        minv = INFTY;
        int u = -1;
        for(int i=0;i<n;i++){
            if(color[i] != BLACK && d[i] < minv){
                u = i;
                minv = d[i];
            }
        }
        if(u == -1)break; //例外処理
        color[u] = BLACK;

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

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

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 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;
   }
}

int main(){
   cin >> n;
   rep(i, n) {
      rep(j, n) {
         M[i][j] = INFTY;
      }
   }

   int k, c, u, v;
   rep(i, n) {
      cin >> u >> k;
      rep(j, k){
         cin >> v >> c;
         M[u][v] = c;
      }
   }

   dijkstra();

   return 0;
}

C++: #include <cstdio>
#include <iostream>
#include <cmath>
#include <ctype.h>
#include <string>
#include <sstream>
#include <iostream>
#include <algorithm>
#include <cstdlib>
#include <map>
#include <queue>
#include <utility>
#include <vector>
#include <set>
#include <list>
#include <cstring>
#include <stack>

using namespace std;

#define mod 1000000007

int main()
{
	int n;
	int graph[101][101] = {};
	cin >> n;
	int ans[101] = {};
	for(int i = 0; i < n; i++){
		ans[i] = -1;
		int u, k;
		cin >> u >> k;
		for(int j = 0; j < k; j++){
			int v, c;
			cin >> v >> c;
			graph[u][v] = c;
		}
	}
	priority_queue<pair<int, int> > qu;
	qu.push(make_pair(0, 0));
	ans[0] = 0;
	while(!qu.empty()){
		int nowd = -(qu.top()).first;
		int nownode = (qu.top()).second;
		qu.pop();
		for(int i = 0; i < n; i++){
			if(graph[nownode][i] == 0) continue;
			int next = nowd + graph[nownode][i];
			if(ans[i] == -1 || ans[i] > next){
				ans[i] = next;
				qu.push(make_pair(-next, i));
			}
		}
	}
	for(int i = 0; i < n; i++){
		cout << i << " " << ans[i] << endl;
	}
}

C++: #include<stdio.h>
#include<algorithm>
#include<iostream>
using namespace std;
#define INF 1000000000
int main()
{
	long long int min,n,u,k,v,c,dist[100][100],s,cost[100],t[100],l=1;
	cin>>n;
	for(int i=0;i<n;i++)
	{
		for(int j=0;j<n;j++)
		{
			dist[i][j]=INF;
			cost[i]=INF;
			t[i]=-1;
		}
	}
	min=INF;
	dist[0][0]=0;
	for(int i=1;i<=5;i++)
	{
		cin>>u;
		cin>>k;
		for(int i=1;i<=k;i++)
		{
			cin>>v>>c;
			dist[u][v]=c;
		}
	}
	s=0;
	cost[s]=0;
	while(l!=n)
	{
		for(int i=0;i<n;i++)
		{
			if(dist[s][i]!=INF)
			{
				if(cost[s]+dist[s][i]<cost[i])
				{
					cost[i]=cost[s]+dist[s][i];
				}
				
			}
		}
		t[s]=1;
		for(int i=1;i<n;i++)
		{
			if(cost[i]<min&&t[i]==-1)
			{
				min=cost[i];
				s=i;
			}
		}
		min=INF+1;
		l++;
	}
	for(int i=0;i<n;i++)
	{
		cout<<i<<" "<<cost[i]<<endl;
	}
	return 0;
}