Go: package main

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

type Node struct {
	Id int
	Dis int
}

type PriorityQueue []*Node

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

func (pq PriorityQueue) Less(i, j int) bool {
	return pq[i].Dis < pq[j].Dis
}

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

func (pq *PriorityQueue) Push(x interface{}) {
	*pq = append(*pq, x.(*Node))
}

func (pq *PriorityQueue) Pop() interface{} {
	n := len(*pq)
	pop := (*pq)[n-1]
	*pq = (*pq)[0:n-1]
	return pop
}

func main() {
	var n int
	fmt.Scan(&n)

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

	g := make([][]int, n)
	c := make([][]int, n)
	pq := make(PriorityQueue, 0, n)
	d := make([]int, n)
	for i := 0; i < n; i++ {
		sc.Scan()
		u, _ := strconv.Atoi(sc.Text())
		sc.Scan()
		k, _ := strconv.Atoi(sc.Text())
		g[u] = make([]int, k)
		c[u] = make([]int, k)
		for j := 0; j < k; j++ {
			sc.Scan()
			g[u][j], _ = strconv.Atoi(sc.Text())
			sc.Scan()
			c[u][j], _ = strconv.Atoi(sc.Text())
		}

		if u == 0 {
			d[u] = 0
		} else {
			d[u] = 1 << 30
		}
		pq.Push(&Node{u, d[u]})
	}
	heap.Init(&pq)

	for pq.Len() > 0 {
		node := heap.Pop(&pq).(*Node)
		for i := 0; i < len(g[node.Id]); i++ {
			nextId := g[node.Id][i]
			nextDis := node.Dis + c[node.Id][i]
			if nextDis < d[nextId] {
				d[nextId] = nextDis
				heap.Push(&pq, &Node{nextId, nextDis})
			}
		}
	}

	wr := bufio.NewWriter(os.Stdout)
	for i := 0; i < n; i++ {
		wr.WriteString(strconv.Itoa(i))
		wr.WriteString(" ")
		wr.WriteString(strconv.Itoa(d[i]))
		wr.WriteString("\n")
	}
	wr.Flush()
}

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

typedef long long ll;

struct Edge {
    ll t,w;
};

struct State {
    ll v;
    ll score;
    bool operator < (const State& tgt) const {
	return score > tgt.score;
    }
};

vector<ll> dijkstra(vector<vector<Edge>>& G, const int start) {
    const ll V = G.size();

    vector<ll>res(V,INT_MAX);
    priority_queue<State> q;
    q.push( State{0,0} );
    while( q.size() ) {
	State s = q.top(); q.pop();
	if( res[s.v] != INT_MAX ) continue;
	res[s.v] = s.score;
	for(auto& e : G[s.v]) {
	    if( res[e.t] != INT_MAX ) continue;
	    q.push( State{e.t, s.score + e.w} );
	}
    }
    return res;
}


int main () {

    ll V; cin >> V;
    vector<vector<Edge>> G(V);
    for(int i=0; i<V; i++) {
	ll u,k; cin >> u >> k;
	for(int j=0; j<k; j++) {
	    ll v,w; cin >> v >> w;
	    G[i].push_back( Edge{v,w} );
	}
    }
    vector<ll> res = dijkstra(G,0);
    for(int i=0; i<V; i++) {
	cout << i << " " << res[i] << endl;
    }    
    return 0;
}

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

typedef pair<int, int> P;

struct Edge {
  int to, cost;
};

int n;
vector<vector<Edge> > G;

vector<int> dij() {
  priority_queue<P, vector<P>, greater<P> > Q;
  vector<int> d(n, -1);
  Q.push({0, 0});
  while ( !Q.empty() ) {
    P p = Q.top(); Q.pop();
    int v = p.second, c = p.first;

    if ( d[v] >= 0 ) continue;
    d[v] = c;
    
    for ( Edge e: G[v] ) {
      Q.push({c+e.cost, e.to});
    }    
  }

  return d;
}

int main() {
  cin >> n;

  G = vector<vector<Edge> >(n);
  for ( int i = 0; i < n; i++ ) {
    int u, k;
    cin >> u >> k;
    for ( int i = 0; i < k; i++ ) {
      int v, c;
      cin >> v >> c;
      G[u].push_back({v, c});      
    }
  }

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

C++: #include <iostream>
#include <vector>
#include <queue>
using namespace std;
static const int MAX = 10000;
static const int INFTY = (1<<21);

int main()
{
  int n;
  vector<pair<int,int>> adj[MAX];

  cin >> 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;
      adj[u].emplace_back(v, c);
    }
  }

  priority_queue<pair<int,int>> PQ;
  int d[MAX];
  bool visited[MAX];
  for (int i = 0; i < n; ++i)
  {
    d[i] = INFTY;
    visited[i] = false;
  }
  d[0] = 0;
  PQ.emplace(0,0);

  while (!PQ.empty())
  {
    pair<int,int> f = PQ.top(); PQ.pop();
    int u = f.second;
    visited[u] = true;
    if (d[u] < f.first * (-1)) continue;

    for (int i = 0; i < adj[u].size(); ++i)
    {
      int v = adj[u][i].first;
      if (visited[v]) continue;
      if (d[v] > d[u] + adj[u][i].second)
      {
        d[v] = d[u] + adj[u][i].second;
        PQ.emplace(d[v] * (-1), v);
      }
    }
  }

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

  return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
struct node{
	int v,c;
	bool operator<(const node&p)const{
		return c>p.c;
	}
};
int d[100005];
vector<node> e[100005];
bool ok[100005];
int n;
void solve(){
	priority_queue<node> q;
	ok[0]=1;
	for(int i=0;i<e[0].size();i++)q.push(e[0][i]);
	int k=1;
	while(k!=n){
		node v=q.top();q.pop();
		if(ok[v.v])continue;
		d[v.v]=v.c;
		ok[v.v]=1;
		k++;
		for(int j=0;j<e[v.v].size();j++)
			q.push({e[v.v][j].v,e[v.v][j].c+v.c});
	}
	for(int i=0;i<n;i++)
		cout<<i<<' '<<d[i]<<"\n";
}
int main(){
//	freopen("a.txt","r",stdin);
	cin.tie(0);
	int u,v,k,c;
	cin>>n;
	while(cin>>u>>k){
		for(int i=0;i<k;i++){
			cin>>v>>c;
			e[u].push_back({v,c});
		}
	}
	solve();
	return 0;
}

C++: #include "bits/stdc++.h"
using namespace std;
typedef long long ll;
typedef vector<vector<pair<int, int> > > vvp;
typedef vector<pair<int,int> > vp;
typedef vector<vector<int> > vvi;
typedef vector<int> vi;
typedef vector<vector<bool> > vvb;
typedef vector<bool> vb;
typedef vector<string> vs;
typedef pair<string, int> psi;
typedef pair<int, int> pii;
#define rep(i,s,n) for(int i = (s); i < (n); i++)
#define all(x) (x).begin(), (x).end()
#define yn(f) (f?"yes":"no")
#define YN(f) (f?"YES":"NO")
#define Yn(f) (f?"Yes":"No")
#define mod 1000000007
#define intmax 2147483647
#define intmin -2147483648
#define longmax 9223372036854775807
#define longmin -9223372036854775808
#define black 0
#define gray 127
#define white 255
int main() {
	int N;
	cin >> N;
	vvp A(N);
	for (int i = 0; i < N; i++)
	{
		int u,k;
		cin >> u>>k;
		for (int j = 0; j < k; j++)
		{
			int v, w;
			cin >> v >> w;
			A[u].push_back(make_pair(v,w));
		}
	}
	vi color(N,black);
	priority_queue<pii,vp,greater<pii> > pq;
	vi mincost(N,intmax);
	color[0] = gray;
	pq.push(make_pair(0,0));
	mincost[0] = 0;
	while (!pq.empty()) {
		pii minp = pq.top();
		pq.pop();
		color[minp.second] = white;
		if (mincost[minp.second]<minp.first) continue; 
		for (int i = 0; i < A[minp.second].size(); i++)
		{
			int u = A[minp.second][i].first;
			if (color[u]!=white&&mincost[u]>mincost[minp.second]+ A[minp.second][i].second) {
				mincost[u] = mincost[minp.second] + A[minp.second][i].second;
				pq.push(make_pair(mincost[u],u));
				color[u] = gray;
			}
		}
	}
	for (int i = 0; i < N; i++)
	{
		cout << i << " " << mincost[i] << endl;
	}
};