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 <cstdio>
#include <cstring>
#include <cstdlib>
#include <cmath>
#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <map>
#include <queue>
#include <utility>
using namespace std;
//_____
#define pb push_back
#define fi first
#define se second
#define mkp make_pair
#define ALL(x) x.begin(),x.end()
#define rep(i,n) for(int i=0; i<(n); ++i)
#define reps(i,f,n) for(int i=(f); i<=(n); ++i)
#define err(...) fprintf(stderr, __VA_ARGS__)
#define show(x) cerr << #x << ':' << x << endl
#define outl(x) cout << (x) << '\n'
#define FAST() cin.tie(0), ios::sync_with_stdio(false)
typedef long long ll;
typedef pair<int,int> pii;
template<class A, class B>inline bool chmax(A &a, B b){return b>a ? a=b,1 : 0;}
template<class A, class B>inline bool chmin(A &a, B b){return b<a ? a=b,1 : 0;}
inline bool inside(int y, int x, int H, int W){return(y>=0 && x>=0 && y<H && x<W);}
const int dx[] = {1, 0, -1, 0,  1, 1, -1, -1};
const int dy[] = {0, 1, 0, -1,  -1, 1, 1, -1};
#define INF 0x3f3f3f3f
#define LEN 1000011
#define NIL -1
//_______

int N;
vector <pii> G[101];
int mcos[101];

void dijkstra(int s)
{
   priority_queue < pii, vector<pii>, greater<pii> > pq;
   pq.push( mkp(0, s) );
   memset( mcos, INF, sizeof(mcos) );
   mcos[s] = 0;

   while( !pq.empty() ){
      const pii tmp = pq.top(); pq.pop();
      if( mcos[tmp.se] < tmp.fi )continue;

      for( const auto& v : G[tmp.se] ){
         const int nc = v.fi + tmp.fi;
         if( chmin( mcos[v.se], nc )) pq.push( mkp(nc, v.se) );
      }
   }
   return ;
}

signed main()
{
   FAST();
   cin >> N;
   rep(i, N){
      int u, k, to, c;
      cin >> u >> k;
      while(k--){
         cin >> to >> c;
         G[i].pb( mkp(c,to) );
      }
   }
   dijkstra(0);
   rep(i, N){
      cout << i << ' ' << mcos[i] << '\n';
   }
}

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

void dijkstra(int s);
const int Infty = 20000000;

int **M,*d,*p,n;
string *color;

int main(){
	cin>>n;
	M = new int*[n]; for(int i=0;i<n;i++) M[i] = new int[n];
	d = new int[n]; p = new int[n]; color = new string[n];
	for(int i=0;i<n;i++){
		for(int j=0;j<n;j++) M[i][j] = -1;
	}

	for(int i=0;i<n;i++){
		int vertex,deg,e,w;
		cin>>vertex>>deg;
		for(int j=0;j<deg;j++){
			cin>>e>>w;
			M[i][e]  = w;
		}
	}

	dijkstra(0);

	for(int i=0;i<n;i++) delete [] M[i]; delete [] M;
	delete [] d; delete [] p; delete [] color;
}

void dijkstra(int s){
	for(int i=0;i<n;i++){
		d[i] = Infty; color[i] = "WHITE";
	}
	d[s] = 0; p[s] = -1;

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

		if(mindist==Infty) break;

		color[u] = "BLACK";

		for(int v=0;v<n;v++){
			if(color[v]!="BLACK" && M[u][v]!=-1){
				if(d[u]+M[u][v]<d[v]){
					d[v] = d[u]+M[u][v];
					p[v] = u;
					color[v] = "GRAY";
				}
			}
		}
	}

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

C++: #include<bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i = 0; i < (n) ; i++)
constexpr auto INF = 2147483647;
typedef long long ll;

static const int MAX = 100;
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

int n, Adj_Marix[MAX][MAX];

void dijkstra(){
  int minv;
  int distance[MAX], color[MAX];
  //init
  for(int i=0;i<n; i++){
    distance[i] = INF;
    color[i] = WHITE;
  }
  distance[0] = 0;
  color[0] = GRAY;
  while(1){
    minv = INF;
    int u  = -1;
    // Find next point
    for(int i =0; i<n; i++){
      if( minv > distance[i] && color[i] != BLACK){
        u = i;
        minv = distance[i];
      }
    }
    //if cant find next point
    if(u == -1) break;
    // Refresh dictance for adj points
    color[u] = BLACK;
    for(int v=0; v<n; v++){
      if(color[v] != BLACK && Adj_Marix[u][v] != INF){
        if(distance[v] > distance[u] + Adj_Marix[u][v]){
          distance[v] = distance[u] + Adj_Marix[u][v];
          color[v] = GRAY;
        }
      }
    }
  }
  for(int i =0; i<n; i++){
    cout << i << " " << (distance[i] == INF ? -1: distance[i] ) << endl;
  }
}

int main(){

  cin >> n;
  rep(i,n){
    rep(j,n){
      Adj_Marix[i][j] = INF;
    }
  }

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

  dijkstra();

  return 0;
}