Go: package main

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

func getScanner(fp *os.File) *bufio.Scanner {
	scanner := bufio.NewScanner(fp)
	scanner.Split(bufio.ScanWords)
	scanner.Buffer(make([]byte, 500001), 500000)
	return scanner
}

func getNextString(scanner *bufio.Scanner) string {
	scanner.Scan()
	return scanner.Text()
}

func getNextInt(scanner *bufio.Scanner) int {
	i, _ := strconv.Atoi(getNextString(scanner))
	return i
}

func main() {
	fp := os.Stdin
	if len(os.Args) > 1 {
		fp, _ = os.Open(os.Args[1])
	}

	scanner := getScanner(fp)
	writer := bufio.NewWriter(os.Stdout)

	n := getNextInt(scanner)

	g := makeGraph(n)
	for i := 0; i < n; i++ {
		u := getNextInt(scanner)
		k := getNextInt(scanner)
		for ii := 0; ii < k; ii++ {
			v := getNextInt(scanner)
			c := getNextInt(scanner)
			g[u][v] = c
		}
	}

	ans := make([]int, n)
	im := make(IntMap, 1)
	im.increment(0)
	for len(im) < n {
		min := 1 << 30
		x := -1
		for u := range im {
			for v := 0; v < n; v++ {
				if im.get(v) != 0 {
					continue
				}
				if min > ans[u]+g[u][v] {
					min = ans[u] + g[u][v]
					x = v
				}
			}
		}
		im.increment(x)
		ans[x] = min
	}

	for i := 0; i < n; i++ {
		fmt.Fprintln(writer, fmt.Sprintf("%d %d", i, ans[i]))
	}
	writer.Flush()
}

func makeGraph(n int) [][]int {
	g := make([][]int, n)
	for i := 0; i < n; i++ {
		g[i] = make([]int, n)
		for ii := 0; ii < n; ii++ {
			g[i][ii] = 1 << 30
		}
	}

	return g
}

// IntMap ...
type IntMap map[int]int

func (m IntMap) get(key int) int {
	if _, ok := m[key]; ok {
		return m[key]
	}
	return 0
}
func (m IntMap) increment(key int) {
	if _, ok := m[key]; ok == false {
		m[key] = 0
	}
	m[key]++
}

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 func(){
  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;
    }
  }
  func();
  return 0;
}

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

struct Node
{
    vector<int> cost;
    vector<int> vertex;

    bool visited = false;
    int minCost = 100000000;
};

int N;
vector<Node> firstNodes(100);

int findNode(const vector<Node>& nodes)
{
    int minCost = 1000000000;
    int index = -1;
    for (int i = 0; i < nodes.size(); i++)
    {
        if(minCost > nodes[i].minCost && !nodes[i].visited)
        {
            minCost = nodes[i].minCost;
            index = i;
        }   
    }
    return index;
}

int main()
{
    cin >> N;
    int u;
    int k;
    int temp;
    for(int i = 0;i < N;i++)
    {
        cin >> u;
        cin >> k;
        for(int i = 0;i < k;i++)
        {
            cin >> temp;
            firstNodes[u].vertex.push_back(temp);
            cin >> temp;
            firstNodes[u].cost.push_back(temp);
        }
    }

    firstNodes[0].minCost = 0;
    
    for(int vi = 0;vi < N;vi++)
    {
        vector<Node> nodes = firstNodes;
        while(nodes[vi].visited != true)
        {
            //find a node that is visited and has minimum cost
            int index = findNode(nodes);

            Node& minNode = nodes[index];
            int vertex;
            int cost;
            minNode.visited = true;
            for (size_t i = 0; i < minNode.vertex.size(); i++)
            {
                vertex = minNode.vertex[i];
                cost = minNode.cost[i];
                nodes[vertex].minCost = min(nodes[vertex].minCost,minNode.minCost + cost);
            }
        }
        cout << vi << " " << nodes[vi].minCost << endl;
    }
}

C++: #include <iostream>
#include <cstdio>
#include <vector>
#include <queue>
#include <utility>
#include <limits.h>

#define DIRECTED true //有向か無向か
#define ull unsigned long long
#define mp(X , Y) make_pair(X , Y)

using namespace std;

bool operator>(const pair<ull,int> a, const pair<ull,int> b){
    return a.first > b.first;
}

class dijkstra{
public:
    int num;
    vector<ull> dist;
    vector<int> prev;

    vector<vector<pair<int,ull>>> side; 

    dijkstra(){
    }

    dijkstra(int n){

        num = n;
        //0オリジンとの混合を避けるため+1する
        for(int i = 0; i < n + 1; i++){
            dist.push_back(ULONG_LONG_MAX);
            prev.push_back(-1);
            vector<pair<int,ull>> v;
            side.push_back(v);
        }
    }

    void reset(){
        dist.clear();
        prev.clear();

        for(int i = 0; i < num + 1; i++){
            dist.push_back(ULONG_LONG_MAX);
            prev.push_back(-1);

        }
    }

    void input(int f, int t,ull d){

        side[f].push_back(mp(t, d));
        if(!DIRECTED) side[t].push_back(mp(f,d));
    }

    void search(int start){
        
        dist[start] = 0;
        prev[start] = 0;

        priority_queue<pair<ull,int>, vector<pair<ull,int>>, greater<pair<ull,int>>> pq;
        pq.push(mp(0,start));

        while(!pq.empty()){
            
            ull d = pq.top().first;
            int s = pq.top().second;

            for(auto itr = side[s].begin(); itr != side[s].end(); itr++){

                ull tmp_d = (*itr).second;
                int to = (*itr).first; 

                if(dist[to] > d + tmp_d){
                    dist[to] = d + tmp_d;
                    prev[to] = s;
                    pq.push(mp(d + tmp_d,to));
                }
            }

            pq.pop();
        }
    }

    ull min_distance(int to){
        return dist[to];
    }

};

int main(){

    int n,u,k;

    cin >> n;

    dijkstra dijk;
    dijk = dijkstra(n);

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

            scanf(" %d %llu",&v,&c);

            dijk.input(u,v,c);

        }
    }

    dijk.search(0);
    for(int i = 0; i < n; i++){
        cout << i << " " << dijk.min_distance(i) << endl;
    }
}