Go: package main

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

const (
	MAX_N      = 10000
	MAX_WEIGHT = 100000
)

type Edge struct {
	start  int
	end    int
	weight int
}

type ShortestInfo struct {
	edges    []Edge
	shortest int
}

type Neighbor struct {
	node   int
	weight int
}

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)

	n, err := nextInt(sc)
	if err != nil {
		panic(err)
	}

	shortestList := make([]ShortestInfo, n)
	for i := 1; i < n; i++ {
		shortestList[i] = ShortestInfo{edges: []Edge{}, shortest: MAX_N*MAX_WEIGHT + 1}
	}

	adjacentMatrix, err := createAdjacentMatrix(n, sc)
	if err != nil {
		panic(err)
	}

	sssp([]int{0}, shortestList, adjacentMatrix)
	for _, v := range shortestList {
		fmt.Printf("%d %d\n", v.getEnd(), v.shortest)
	}
}

func (si ShortestInfo) getEnd() int {
	if len(si.edges) == 0 {
		return 0
	} else {
		return si.edges[len(si.edges)-1].end
	}
}

func createAdjacentMatrix(n int, sc *bufio.Scanner) ([][]Neighbor, error) {
	adjacentMatrix := make([][]Neighbor, n)
	for i := 0; i < n; i++ {
		id, err := nextInt(sc)
		if err != nil {
			return nil, err
		}
		adjacentMatrix[id] = []Neighbor{}
		vertexNum, err := nextInt(sc)
		if err != nil {
			return nil, err
		}
		for j := 0; j < vertexNum; j++ {
			v, err := nextInt(sc)
			if err != nil {
				return nil, err
			}
			c, err := nextInt(sc)
			if err != nil {
				return nil, err
			}
			adjacentMatrix[id] = append(adjacentMatrix[id], Neighbor{v, c})
		}
	}
	return adjacentMatrix, nil
}

func sssp(nodeStack []int, shortestList []ShortestInfo, adjacentMatrix [][]Neighbor) {
	for len(nodeStack) > 0 {
		currentNode := nodeStack[0]
		nodeStack = nodeStack[1:]
		currentShortest := getShortest(currentNode, shortestList)
		adjacents := findAdjacents(currentNode, adjacentMatrix)
		for i := 0; i < len(adjacents); i++ {
			adj := adjacents[i]
			if currentShortest.shortest+adj.weight < getShortest(adj.end, shortestList).shortest {
				setShortest(adj.end, adj, currentShortest, shortestList)
				nodeStack = append(nodeStack, adj.end)
			}
		}
	}
}

func getShortest(node int, shortestList []ShortestInfo) ShortestInfo {
	return shortestList[node]
}

func setShortest(node int, edge Edge, currentShortest ShortestInfo, shortestList []ShortestInfo) {
	newEdges := make([]Edge, len(currentShortest.edges)+1)
	for i := 0; i < len(newEdges)-1; i++ {
		newEdges[i] = currentShortest.edges[i]
	}
	newEdges[len(newEdges)-1] = edge
	shortestInfo := ShortestInfo{edges: newEdges, shortest: currentShortest.shortest + edge.weight}
	shortestList[node] = shortestInfo
}

func findAdjacents(currentNode int, adjacentMatrix [][]Neighbor) []Edge {
	adjacents := adjacentMatrix[currentNode]
	edges := []Edge{}
	for _, neighbor := range adjacents {
		edges = append(edges, Edge{start: currentNode, end: neighbor.node, weight: neighbor.weight})
	}
	return edges
}

func nextInt(sc *bufio.Scanner) (int, error) {
	sc.Scan()
	return strconv.Atoi(sc.Text())
}

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

struct Edge {
  /*
    dst -> destination
    weight -> weight
   */
  int dst,weight;
};

struct Data {

  int place,min;

  bool operator < (const Data& data)const{
    //if( min < data.min ) => true;
    if(data.min != min)return min > data.min;
    return data.place > place;
  }

};

//int cost[100001][100001];
vector<Edge> cost[10001];
int n;
int mindist[10001];
bool used[10001];

void dijkstra(){

  for(int i=0 ; i < 10001 ; i++){
    mindist[i]=1e9;
  }
  
  mindist[0]=0;

  priority_queue<Data> PQ;

  PQ.push((Data){0,0});

  while(!PQ.empty()){
    Data a=PQ.top();
    PQ.pop();
    if( mindist[a.place] < a.min ) continue;
    for(int i=0 ; i < (int)cost[a.place].size() ; i++){
      if(mindist[cost[a.place][i].dst] > cost[a.place][i].weight+mindist[a.place]){
	mindist[cost[a.place][i].dst] = cost[a.place][i].weight+mindist[a.place];
	PQ.push((Data){cost[a.place][i].dst,mindist[cost[a.place][i].dst]});
      }
      //cost[a.place].pop_back();
    } 
  }
  
  for(int i=0 ; i < n ; i++){
    cout <<i<<" "<<mindist[i]<<endl;
  }
  
}
int main(){
  
  int u,k,v,c;
  
  // 0 -> 1 weight : 3
  /*  
      cost[0].push_back((Edge){1,3});
      cost[0].push_back((Edge){0,4});
      cost[2].push_back((Edge){0,3});
  */
  
  cin >>n;
  
  for(int i=0 ; i < n ; i++){
    cin >>u>>k;
    for(int j=0 ; j < k ; j++){
      cin >>v>>c;
      cost[u].push_back((Edge){v,c});
    }
  }

  dijkstra();

  return 0;
}


/*
1sec => 10^8


 */

C++: #include <algorithm>
#include <iostream>
#include <vector>
using namespace std;
const long long INF = 1LL << 60;    // 1.15x10^18
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }

using edge = pair<int, long long>;
using Graph = vector<vector<edge>>;

vector<long long> dijkstra(const Graph &g, int s) {
    int n = g.size();
    vector<long long> dist(n, INF);
    vector<bool> fixed(n);
    dist[s] = 0;
    while (true) {
        int u = -1;
        for (int i = 0; i < n; i++) if (!fixed[i]) {
            if (u == -1 || dist[i] < dist[u]) u = i;
        }
        if (u == -1) break;
        fixed[u] = true;
        for (auto &e: g[u]) chmin(dist[e.first], dist[u] + e.second);
    }
    return dist;
}

int main() {
    int V; cin >> V;
    Graph g(V);
    for (int i = 0; i < V; i++) {
        int u, k; cin >> u >> k;
        while (k--) {
            int v, c; cin >> v >> c;
            g[u].emplace_back(v, c);
        }
    }
    auto dist = dijkstra(g, 0);
    for (int u = 0; u < V; u++) cout << u << " " << dist[u] << endl;
    return 0;
}

C++: #include<iostream>
#include<algorithm>
#include<queue>
#include<vector>
#include<stdio.h>
using namespace std;

static const int INFTY = (1<<21);
enum Color{
    WHITE,
    GRAY,
    BLACK
};
int n;

//int M[100][100];
vector<pair<int,int> > adj[10000];   //隣接リスト
priority_queue<pair<int, int> > PQ; 
Color color[10000];
int d[10000];

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

        for(int j=0, size = adj[u].size(); j<size;  j++){
            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;
            }
        }
    }

    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++){
        int u, k;
        cin >> u >> k;
        for(int j=0; j<k; j++){
        int v, g;
        cin >> v >> g;
        adj[u].push_back(make_pair(v, g));
        }
    }

    dijkstra();
    return 0;
}