Go: package main

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

const (
	white int = iota
	gray
	black
)

type node struct {
	id     int
	parent int
	edge   []int
	weight []int
	color  int
}

type graph struct {
	nodes    []node
	distance []int
}

var infty = 1 << 32
var null = -1

func constructgraph() *graph {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	n := nextInt(sc)

	g := &graph{make([]node, n), make([]int, n)}

	for i := 0; i < n; i++ {
		id := nextInt(sc)
		edges := nextInt(sc)
		n := node{}
		n.id = id
		n.edge = make([]int, edges)
		n.weight = make([]int, edges)
		n.color = white
		for j := 0; j < edges; j++ {
			to := nextInt(sc)
			w := nextInt(sc)
			n.edge[j] = to
			n.weight[j] = w
		}
		g.nodes[id] = n
	}
	return g
}

func nextInt(sc *bufio.Scanner) int {
	sc.Scan()
	v, _ := strconv.Atoi(sc.Text())
	return v
}

func (g *graph) preparedijkstra(s int) {
	for i := 0; i < len(g.nodes); i++ {
		g.nodes[i].color = white
		g.nodes[i].parent = null
		g.distance[i] = infty
	}
	g.distance[s] = 0
}

func (g *graph) dijkstra(s int) []int {
	g.preparedijkstra(s)

	for {
		var u int
		mincost := infty
		for i, d := range g.distance {
			if g.nodes[i].color != black && mincost > d {
				mincost = d
				u = i
			}
		}

		if mincost == infty {
			break
		}

		g.nodes[u].color = black

		for i, e := range g.nodes[u].edge {
			if g.nodes[e].color != black {
				if g.distance[e] > g.distance[u]+g.nodes[u].weight[i] {
					g.distance[e] = g.distance[u] + g.nodes[u].weight[i]
					g.nodes[e].parent = u
					g.nodes[e].color = gray
				}
			}
		}
	}
	return g.distance
}

func printShortestPath(d []int) {
	for i, v := range d {
		fmt.Printf("%d %d\n", i, v)
	}
}

func main() {
	g := constructgraph()
	d := g.dijkstra(0)
	printShortestPath(d)
}

C++: #include<iostream>
#include<vector>
#include<queue>
#define INF 2e9
using namespace std;

void Dikstra(const vector<vector<pair<int, int> > >& G, vector<int>& d){
    d[0] = 0;
    priority_queue<pair<int, int> , vector<pair<int, int> >, greater<pair<int, int> > > PQ;
    PQ.push(make_pair(0, 0));
    vector<bool> is_black(d.size(), false);
    is_black[0] = true;
    while (!PQ.empty()) {
        int t = PQ.top().second;
        PQ.pop();
        is_black[t] = true;
        for (int i = 0; i < G[t].size(); i++) {
            int v = G[t][i].first;
            int w = G[t][i].second;
            if (!is_black[v] && d[t] + w < d[v]) {
                bool flag = false;
                if (d[v] == INF) flag = true;
                d[v] = d[t] + w;
                if (flag) PQ.push(make_pair(d[v], v));
            }
        }
    }

}

int main(){
    int n;
    cin >> n;
    vector<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));
        }
    }
    vector<int> d(n, INF);
    Dikstra(G, d);
    for (int i = 0; i < n; i++) {
       cout << i << " " << d[i] << endl;
    }

    return 0;
}

C++: #include <iostream>
#include <cstdlib>
#include <cstdio>
#include <vector>
#include <algorithm>
#include <set>
#include <cstring>
#include <cmath>
using namespace std;

#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define REP(i, k, n) for (int i = (int)(k); i < (int)(n); i++)
#define rrep(i, n) for (int i = (int)(n)-1; i >= 0; i--)
#define rREP(i, k, n) for (int i = (int)(n)-1; i >= k; i--)

#define debug(x) cerr<<#x<<": "<<x<<'\n'

#define fi first
#define se second

#define vi vector<int>
#define pb push_back
#define mp make_pair

#define pcnt __builtin_popcount

typedef long long ll;

const ll inf = 99900100100;
const int MOD = 998244353;
const double EPS = 1e-9;

vector<vector<pair<int,int> > > G(1100);

int main(){
    cin.tie(0);
    ios_base::sync_with_stdio(false);
    int n;
    cin >> n;
    rep(i,n){
      int u,k;
      cin >> u >> k;
      rep(j,k){
        int v,c;
        cin >> v >> c;
        G[u].push_back(mp(v,c));
      }
    }
    ll d[1100] = {};
    rep(i,1100) d[i] = inf;
    d[0] = 0LL;
    while(true){
        bool update = false;
        rep(i,n){
          for(auto o : G[i]){
            if(d[o.fi] > d[i]+o.se){
                d[o.fi] = d[i]+o.se;
                update = true;
            }
          }
        }
        if(!update) break;
    }
    rep(i,n) cout << i << " " << d[i] << endl;
    return 0;
}

C++: #include<iostream>
using namespace std;
static const int INF=(1<<21);
static const int WHI=0;
static const int BLA=2;
static const int GR=1;

int n,M[100][100];

void dijkstra(){
  int minv;
  int a[100],color[100];
  for (int i=0;i<n;i++){
    a[i]=INF;
    color[i]=WHI;
  }

  
  color[0]=GR;
  a[0]=0;
  while(1){
    minv=INF;
    int e =-1;
    for (int i=0;i<n;i++){
      if(minv>a[i]&&color[i]!=BLA){
	minv=a[i];
	e=i;
      }
    }
    
    if(e==-1)break;
    color[e]=BLA;
    for(int v=0;v<n;v++){
      if(color[v]!=BLA && M[e][v]!=INF){
	if(a[v]>a[e]+M[e][v]){
	  a[v]=a[e]+M[e][v];
	  color[v]=GR;
	}
      }
    }
  }
  for(int i=0;i<n;i++){
    cout<<i<<" "<<(a[i]==INF ? -1 : a[i]) << endl;
  }
}

int main(){
  int k,m,e,v;
  
  cin>>n;
  for(int i=0;i<n;i++){
    for(int j=0;j<n;j++){
      M[i][j]=INF;
    }
  }
  for(int i=0;i<n;i++){
    cin>>e>>k;
    for(int j=0;j<k;j++){
      cin>>v>>m;
      M[e][v]=m;
      
    }
  }
  dijkstra();
}

C++: #include<iostream>
#define INF 1<<21
using namespace std;
static const int N = 101;
int n,A[N][N];
void dikstra(void){
    int d[N],p[N],color[N],minv;
    for(int i=0;i<n;i++){
        d[i] = INF;
        p[i] = -1;
        color[i] = 0;
    }
    d[0] = 0;
    while(1){
        int u =-1;
        minv = INF;
        for(int i=0;i<n;i++){
            if(d[i]<minv && color[i]!=1){
                u = i;
                minv = d[i];
            }
        }
        if(u==-1){
            break;
        }
        color[u] = 1;
        for(int v=0;v<n;v++){
            if(d[u]+ A[u][v] < d[v]){
                d[v] = d[u] + A[u][v];
                p[v] = u;
            }
        }
    }
    for(int i=0;i<n;i++){
        cout << i << ' ' << d[i] << endl;
    }
}
int main(void){
    int u,adj,v;
    cin >> n;
    for(int i=0;i<n;i++){
        for(int j=0;j<n;j++){
            A[i][j] = INF;
        }
    }
    for(int i=0;i<n;i++){
        cin >> u >> adj;
        for(int j=0;j<adj;j++){
            cin >> v >> A[u][v];
        }
    }
    dikstra();
    return 0;
}