Go: package main

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

func main() {
	r := bufio.NewReader(os.Stdin)

	var n int
	fmt.Fscan(r, &n)
	cs := make([]map[int]int, n) // []v_i -> c_i
	for h := 0; h < n; h++ {
		var u, k int
		fmt.Fscan(r, &u, &k)
		m := make(map[int]int)
		for i := 0; i < k; i++ {
			var v, c int
			fmt.Fscan(r, &v, &c)
			m[v] = c
		}

		cs[u] = m
	}

	q := make(map[int]int)
	q[0] = 0
	visited := make(map[int]struct{})
	out := make([]int, n)

	for len(q) > 0 {
		u := top(q)
		for uu, c := range cs[u] {
			// Consider the connection between u and uu.
			if _, ok := visited[uu]; ok {
				continue
			}
			if d, ok := q[uu]; !ok || d > q[u]+c {
				q[uu] = q[u] + c
			}
		}

		out[u] = q[u]
		delete(q, u)
		visited[u] = struct{}{}
	}

	for u, d := range out {
		fmt.Println(u, d)
	}
}

func top(q map[int]int) int {
	minu := -1
	min := -1
	for u, d := range q {
		if min < 0 || d < min {
			minu = u
			min = d
		}
	}

	return minu
}

C++: #include<bits/stdc++.h>
#define ll long long
using namespace std;
const int INF = 0x3f3f3f;
int a[300][300];
int vis[300];	//标记是否访问过 
int path[300];	//从起点到该点的距离 
int n;
void Dijkstra(int s)
{
	int min,pos;
	
	memset(vis,0,sizeof(vis));
	
	path[s] = 0;
	vis[s]  = 1;
	
	for(int i = 0; i < n; i++)
	{
		path[i] = a[s][i];
	}
	
	for(int i = 1; i < n; i++)
	{
		min = INF;
		for(int j = 0; j < n; j++)
		{
			if( path[j] < min && !vis[j])
			{
				pos = j;
				min = path[j];
			}
		}
		
		vis[pos] = 1;
		
		for(int j = 0;j < n;j++)
		{
			if(path[pos] + a[pos][j] < path[j] && !vis[j])
			{
				path[j] = path[pos] + a[pos][j];
			}
		}
	}
}

int main()
{
	int m;
	while(scanf("%d",&n)!=EOF)
	{
		for(int i=0;i<n;i++)
		{
			for(int j=0;j<n;j++)
			{
				a[i][j] = INF;
			}
			
			a[i][i] = 0;
		}
		
		for(int i = 0;i<n;i++)
		{
			int x,y,k,l;
			scanf("%d%d",&x,&k);
			
			for(int j=0;j<k;j++)
			{
				scanf("%d%d",&y,&l);
				
				if(a[x][y] > l)
				{
					a[x][y] = l;
				//	a[y][x] = l;
				}
			}
		}
			
			
			
		Dijkstra(0);
		
		for(int i=0;i<n;i++)
		{
			printf("%d %d\n",i,path[i]);
		}
				
	}

}

C++: #include<iostream>
#include<vector>
#include<algorithm>
#define MAX_V 100
#define INF 1e9
using namespace std;
int cost[MAX_V][MAX_V];
int d[MAX_V];
bool used[MAX_V];
int V;//頂点数

void dijkstra(int s)
{
	for (int i = 0; i < MAX_V; i++)
	{
		d[i] = INF;
		used[i] = false;
	}
	d[s] = 0;

	while (true)
	{
		int v = -1;
		for (int u = 0; u < V; u++)
		{
			if (!used[u] && (v == -1 || d[u]<d[v]))
			{
				v = u;
			}
		}
		if (v == -1)
		{
			break;
		}
		used[v] = true;

		for (int u = 0; u < V; u++)
		{
			d[u] = min(d[u], d[v] + cost[v][u]);
		}
	}
	

}




int main()
{
	for (int i = 0; i < MAX_V; i++)
	{
		for (int j = 0; j < MAX_V; j++)
		{
			cost[i][j] = INF;
		}
	}
	cin >> V;
	for (int i = 0; i < V; i++)
	{
		int u;//頂点番号
		cin >> u;
		int k;//出次数
		cin >> k;
		for (int j = 0; j < k; j++)
		{
			int v;
			cin >> v;
			int c;
			cin >> c;
			cost[u][v] = c;
	    }

	}

	dijkstra(0);

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

C++: #include <iostream>
#include <vector>
#include <queue>
const int inf=1e9;
using namespace std;
int main(){

  int n,now=0;
  priority_queue < pair<int,int>, vector<pair<int,int> >, greater<pair<int,int> > > g[100000];
  cin>>n;
  for(int i=0,u,k,v,c;i<n&&cin>>u>>k;i++) for(int j=0;j<k&&cin>>v>>c;j++) g[u].push(make_pair(c,v));
  int flag[100]={},c[100]={};
  for(int i=1;i<n;i++) c[i]=inf;
  for(int i=0;i<n;i++){
    int next=g[now].top().second,cnt=0;
    for(;!g[now].empty();g[now].pop()) if(!flag[g[now].top().second]){
        c[g[now].top().second]=min(c[g[now].top().second],c[now]+g[now].top().first);
        if(!cnt) next=g[now].top().second;
        cnt++;
      }
    flag[now]=1;
    now=next;
  }
  for(int i=0;i<n;i++) cout<<i<<" "<<c[i]<<endl;
  return 0;

}

C++: #include<bits/stdc++.h>
using namespace std;
#define int long long
int e[111][111],d[111];
int used[111];
signed main(){
  int n;
  cin>>n;
  int INF=1LL<<55LL;
  for(int i=0;i<n;i++)
    for(int j=0;j<n;j++)
      e[i][j]=INF;
  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;
      e[u][v]=min(e[u][v],c);
    }
  }
  memset(used,0,sizeof(used));
  for(int i=0;i<n;i++) d[i]=INF;
  d[0]=0;
  while(1){
    int u=-1;
    for(int i=0;i<n;i++){
      if(used[i]) continue;
      if(d[i]==INF) continue;
      if(u<0||d[i]<d[u]) u=i;
    }
    if(u<0) break;
    used[u]=1;
    for(int i=0;i<n;i++){
      d[i]=min(d[i],d[u]+e[u][i]);
    }
  }
  for(int i=0;i<n;i++) cout<<i<<" "<<d[i]<<endl;
  return 0;
}

C++: #include <bits/stdc++.h>

#define rep(n) for(int i=0;i<n;i++)
#define repp(j, n) for(int j=0;j<n;j++)
#define reppp(i, m, n) for(int i=m;i<n;i++)
#define all(c) c.begin(), c.end()
#define rall(c) c.rbegin(), c.rend()

using namespace std;

typedef long long ll;
typedef pair<ll, ll> Pll;
typedef pair<int, int> Pii;
struct edge{int from, to; ll cost;};

const ll MOD = 1000000007;
const double EPS = 1e-9;

map<ll, ll> d;
priority_queue< Pll, vector<Pll>, greater<Pll> > que;
map<ll, vector<Pll> > edges;

void dijkstra(ll start){
    d[start] = 0;
    que.push(Pll(0, start));

    while(!que.empty()){
        Pll v = que.top(); que.pop();
        if(d.find(v.second) != d.end() && d[v.second] < v.first) continue;
        rep(edges[v.second].size()){
            Pll e = edges[v.second][i];
            if(d.find(e.first) == d.end() || d[e.first] > d[v.second] + e.second){
                d[e.first] = d[v.second] + e.second;
                que.push(Pll(d[e.first], e.first));
            }
        }
    }
}

int main(){
    std::ios::sync_with_stdio(0); cin.tie(0);
    int n;
    cin >> n;

    rep(n){
        ll u, k, c, v;
        cin >> u >> k;
        repp(j, k){
            cin >> v >> c;
            edges[u].emplace_back(v, c);
        }
    }

    dijkstra(0);
    repp(u, n){
        cout << u << " " << d[u] << endl;
    }

}

C++: #include<iostream>
using namespace std;
#define max 100
#define infty 1<<21

int n;
int d[max];
int aa[max][max];
int color[max];

void soya() {
	d[0] = 0;
	while (1) {
		int x = infty;
		for (int i = 0; i < n; i++) {
			if (x != infty) {
				if (d[i] < d[x] && color[i] != 2) {
					x = i;
				}
			}
			else {
				if (d[i] < x && color[i] != 2) {
					x = i;
				}
			}
		}

		if (x == infty) break;
		else {
			color[x] = 2;
			for (int i = 0; i < n; i++) {
				if (aa[x][i] != -1 && d[x] + aa[x][i] < d[i]) {
					d[i] = d[x] + aa[x][i];
				}
			}
		}
	}
}

int main() {
	for (int i = 0; i < max; i++) {
		color[i] = 0;
		d[i] = infty;
	}

	for (int i = 0; i < max; i++) {
		for (int j = 0; j < max; j++) {
			aa[i][j] = -1;
		}
	}

	cin >> n;
	for (int i = 0; i < n; i++) {
		int id;
		int k;
		cin >> id >> k;
		for (int j = 0; j < k; j++) {
			int num1;
			int kyori;
			cin >> num1 >> kyori;
			aa[id][num1] = kyori;
		}
	}

	soya();

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

	return 0;
}