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
}

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) ([][]int, error) {
	adjacentMatrix := make([][]int, n)
	for i := 0; i < n; i++ {
		id, err := nextInt(sc)
		if err != nil {
			return nil, err
		}
		adjacentMatrix[id] = make([]int, n)
		for j := 0; j < n; j++ {
			adjacentMatrix[id][j] = -1
		}
		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][v] = c
		}
	}
	return adjacentMatrix, nil
}

func sssp(nodeStack []int, shortestList []ShortestInfo, adjacentMatrix [][]int) {
	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 [][]int) []Edge {
	adjacents := adjacentMatrix[currentNode]
	edges := []Edge{}
	for i, v := range adjacents {
		if v >= 0 {
			edges = append(edges, Edge{start: currentNode, end: i, weight: v})
		}
	}
	return edges
}

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

C++: #include<bits/stdc++.h>
using namespace std;

#define rep(i,n) for(int i = 0; i < n; i++)
#define Rep(i,n) for(int i = 1; i <= n; i++)
#define sz(x) int(x.size())
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
#define YesorNo(a) printf(a ? "Yes\n" : "No\n")
#define endl '\n'
#define fi first
#define se second
using ll = long long;
using P = pair<int,int>;
using Pl = pair<ll,ll>;
template<class T> using V = vector<T>;
const int dx[] = {0,1,0,-1,1,1,-1,-1};
const int dy[] = {1,0,-1,0,1,-1,-1,1};
const int inf = (1<<30)-1;
const ll infll = (1LL<<62)-1;
ll ceil(const ll &a, const ll &b){return ((a)+(b)-1)/b;}
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; }
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; }


void Dijkstra(int s, const vector<vector<P>> &g, vector<int> &dis) {
  priority_queue<P, vector<P>, greater<P>> que; // pair = (cost, v);
  dis[s] = 0;
  que.emplace(0,s);
  while(!que.empty()) {
    P p = que.top(); que.pop();
    int now = p.second;
    if(dis[now] < p.first) continue;
    for(P np : g[now]) {
      int next = np.second;
      if(dis[next] > dis[now] + np.first) {
        dis[next] = dis[now] + np.first;
        que.emplace(dis[next], next);
      }
    }
  }
}


int main(){
    
    int n;
    cin >> n;
    V<V<P>> g(n); // pair = (cost, to);
    rep(i,n) {
        int a, k;
        cin >> a >> k;
        rep(j,k) {
            int b, v;
            cin >> b >> v;
            g[a].emplace_back(v,b);
        }
    }

    V<int> d(n, inf);
    Dijkstra(0,g,d);
    rep(i,n) {
        printf("%d %d\n", i, d[i]);
    }
}

C++: #include <iostream>
#include <cstdio>
#include <vector>
#include <climits>
#include <queue>

#define INF INT_MAX

using namespace std;

int main(){
  int n; cin >> n;
  vector<pair<int,int> > G[n];
  for(int i=0;i<n;i++){
    int u,k; cin >> u >> k;
    for(int j=0;j<k;j++){
      int v,c; cin >> v >> c;
      G[u].push_back(make_pair(v,c));
    }
  }
  //dijkstra from 0
  priority_queue<pair<int,int>,vector<pair<int,int> >,greater<pair<int,int> > > PQ;
  int visited[n],d[n];
  for(int i=0;i<n;i++){
    visited[i]=0;
    d[i]=INF;
  }
  d[0]=0;
  PQ.push(make_pair(d[0],0));
  while(PQ.empty()==false){
    int u=PQ.top().second;
    int u_first=PQ.top().first;
    PQ.pop();
    //cout << "u:" << u << endl;
    visited[u]=1;
    if(d[u]<u_first) continue;
    for(int i=0;i<G[u].size();i++){
      int v=G[u][i].first;
      //cout << "v:" << v << endl;
      if(visited[v]==0){
        if(d[u]+G[u][i].second<d[v]){
          d[v]=d[u]+G[u][i].second;
          PQ.push(make_pair(d[v],v));
        }
      }
    }
  }
  for(int i=0;i<n;i++) cout << i << " " << d[i] << endl;
}

C++: #include<iostream>
#include<algorithm>
#include<vector>
#include<queue>
#define MAX 10000
#define INF (1 << 21)
#define WHITE  1
#define GRAY  2
#define BLACK  3
using namespace std;

int n;
vector<pair<int, int> > adj[MAX];

void dijkstra(){
  priority_queue<pair<int, int> > pq;

  vector<int> color(MAX);
  vector<int> d(MAX);
  
  for(int i = 0; i < n; i++){
    d[i] = INF;
    color[i] = WHITE;
  }

  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 i = 0; i < adj[u].size(); i++){
      int v = adj[u][i].first;

      if(color[v] == BLACK) continue;
      if(d[v] > d[u] + adj[u][i].second){
	d[v] = d[u] + adj[u][i].second;
	pq.push(make_pair(d[v] * (-1), v));
	color[v] = GRAY;
      }
    }
  }

  for(int i = 0; i < n; i++){
    cout << i << " " << (d[i] == INF ? -1:d[i]) << endl;
  }
}

int main()
{
  int k, u, v, c;

  cin >> n;

  for(int i = 0; i < n; i++){
    cin >> u >> k;

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

  dijkstra();

  return 0;

}