Go: package main

import (
	"bufio"
	"container/heap"
	"fmt"
	"os"
	"strconv"
)

//make priority queue
type Item struct {
	id       int
	priority int // this state is priority and distans from start
	index    int
}

type PriorityQueue []*Item

func (pq PriorityQueue) Len() int { return len(pq) }

// we want the ascending-priority-queue.
// So we use less than here.
func (pq PriorityQueue) Less(i, j int) bool {
	return pq[i].priority < pq[j].priority
}

func (pq PriorityQueue) Swap(i, j int) {
	pq[i], pq[j] = pq[j], pq[i]
	pq[i].index = j
	pq[j].index = i
}

func (pq *PriorityQueue) Push(x interface{}) {
	n := len(*pq)
	item := x.(*Item)
	item.index = n
	*pq = append(*pq, item)
}

func (pq *PriorityQueue) Pop() interface{} {
	old := *pq
	n := len(old)
	item := old[n-1]
	item.index = -1 //for safety
	*pq = old[0 : n-1]
	return item
}

func (pq *PriorityQueue) update(dist int, id int) {
	for _, i := range *pq {
		if i.id == id {
			if i.priority > dist {
				i.priority = dist
			}
		}
	}
}

// the main code
func nextInt(sc *bufio.Scanner) int {
	sc.Scan()
	n, _ := strconv.Atoi(sc.Text())
	return n
}

func dikstra(dist [][]int, n int) []int {
	// preparate priority queue
	inf := 1 << 30
	pq := make(PriorityQueue, n)
	shortests := make([]int, n)
	for i := 0; i < n; i++ {
		pq[i] = &Item{
			id:       i,
			priority: inf,
			index:    i,
		}

		shortests[i] = inf
	}
	pq[0].priority = 0
	shortests[0] = 0

	for pq.Len() > 0 {
		item := heap.Pop(&pq).(*Item)
		shortests[item.id] = item.priority
		for id, d := range dist[item.id] {
			if d != -1 {
				pq.update(item.priority+d, id)
			}
		}
		heap.Init(&pq)
	}
	return shortests
}

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

	// init
	n := nextInt(sc)
	dist := make([][]int, n)
	for i := 0; i < n; i++ {
		dist[i] = make([]int, n)
		for j := 0; j < n; j++ {
			dist[i][j] = -1
		}
	}

	// std Input
	for i := 0; i < n; i++ {
		u := nextInt(sc)
		k := nextInt(sc)
		for j := 0; j < k; j++ {
			v, c := nextInt(sc), nextInt(sc)
			dist[u][v] = c
		}
	}

	shortests := dikstra(dist, n)
	for i, d := range shortests {
		fmt.Printf("%d %d\n", i, d)
	}
}

C++: #include<iostream>
#include<algorithm>
#include<queue>
using namespace std;
static const int MAX = 10000;
static const int INFTY = (1<<20);
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

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

void dijkstra(void);

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;
}

void dijkstra(void)
{
  priority_queue<pair<int, int> > PQ;
  int color[MAX];
  int d[MAX];
  for( int i = 0; i < n; i++)
    {
      d[i] = INFTY;
      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 j = 0; j < adj[u].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;
    }
}

C++: #include <iostream>
#include <cstdio>
#include <algorithm>
#include <vector>
#include <queue>
using namespace std;
const int maxx=10010;
const int infinity=1<<30;

int main() {
	int n,a,b,c,e;
	vector<pair<int, int> > A[maxx];
	bool flag[maxx];
	int d[maxx];
	cin>>n;
	for(int i=0;i<n;i++){
		cin>>a>>b;
		for(int j=0;j<b;j++){
			cin>>c>>e;
			A[a].push_back(make_pair(c,e));
		}
	}
	for(int i=0;i<n;i++){
		flag[i]=false;
		d[i]=infinity;
	}
	priority_queue<pair<int,int> > PQ;
	d[0]=0;
	PQ.push(make_pair(0, 0));
	while(PQ.empty()==0){
		pair<int, int> u=PQ.top();
		PQ.pop();
		//cout<<u.first<<" "<<d[u.first]<<endl;
		flag[u.second]=true;
		int len=A[u.second].size();
		for(int i=0;i<len;i++){
			int v=A[u.second][i].first;
			if(flag[v]==false && d[u.second]+A[u.second][i].second<d[v]){
				d[v]=d[u.second]+A[u.second][i].second;
				PQ.push(make_pair(d[v]*(-1),v));
			}
		}
	}

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

	return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
typedef unsigned long long ull;
typedef long long ll;
typedef pair<int, int> P;
map <int,int> mp;
vector<int> V;
#define INF (1<<30)
#define INFLL (1ll<<60)
#define EPS (1e-10)
static const int MAX=1e5;
static const int MOD=1e9+7;
static const int NMAX=50;
static const int MMAX=50;
int dx[4]={0,1,0,-1},dy[4]={-1,0,1,0};
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

int N;
int d[MAX];
vector<P> adj[MAX]; //<隣接地点,その地点の最短距離>
void dijkstra(int s){
    priority_queue<P> PQ; //<最短距離*-1,場所>
    int color[MAX];
    for(int i=0;i<N;i++){
        d[i]=INF;
        color[i]=WHITE;
    }
    
    d[s]=0;
    PQ.push(make_pair(0,0));
    color[0]=GRAY;
    
    while(!PQ.empty()){
        P f=PQ.top(); PQ.pop();
        int u=f.second; //次に行く場所の候補
        
        color[u]=BLACK;
        
        if(d[u]<f.first*(-1)) continue; //候補の今の時点の最短距離が、記録されてるのより小さい
        
        for(int j=0;j<adj[u].size();j++){
            int v=adj[u][j].first; //uのj番目の隣接地点のインデックス
            if(color[v]==BLACK) continue; //もう行った
            if(d[v]<=d[u]+adj[u][j].second)continue;//vにはもっと早い行き方がある
            d[v]=d[u]+adj[u][j].second;
            PQ.push(make_pair(d[v]*(-1),v));
            color[v]=GRAY;
        }
        
    }
}


int main(){
    cin.tie(0);  ios::sync_with_stdio(false);
    
    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(0);
    for(int i=0;i<N;i++)
        cout<<i<<" "<<(d[i]==INF?-1:d[i])<<"\n";
    
    return 0;
}

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

using weight = int;

struct edge {
    int to;
    weight cost;
};

using edges = std::vector<edge>;
using graph = std::vector<edges>;

// when g has neg cycle, second -> false
std::pair<std::vector<weight>, bool> spfa(graph const& g, int s) {
    constexpr weight inf = std::numeric_limits<weight>::max() / 2;
    const int n = g.size();
    std::vector<weight> d(n, inf);
    std::vector<int> in_q(n), count(n);
    std::queue<int> que;
    d[s] = 0;
    que.emplace(s);
    in_q[s] = true;
    ++count[s];
    bool neg_cycle = false;
    [&]() {
        while(!que.empty()) {
            int v = que.front();
            que.pop();
            in_q[v] = false;
            for(auto& e : g[v]) {
                if(d[v] != inf && d[e.to] > d[v] + e.cost) {
                    d[e.to] = d[v] + e.cost;
                    if(!in_q[e.to]) {
                        que.emplace(e.to);
                        in_q[e.to] = true;
                        ++count[e.to];
                        if(count[e.to] >= n) {
                            neg_cycle = true;
                            return;
                        }
                    }
                }
            }
        }
    }();

    return std::make_pair(d, !neg_cycle);
}

using namespace std;

int main() {
    int n;
    cin >> n;
    graph 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(edge{v, c});
        }
    }

    auto ans = spfa(g, 0).first;
    for(int i = 0; i < n; ++i) {
        cout << i << ' ' << ans[i] << endl;
    }
}