Go: package main

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

type Item struct {
	value    int // The value of the item; arbitrary.
	priority int // The priority of the item in the queue.
	// The index is needed by update and is maintained by the heap.Interface methods.
	index int // The index of the item in the heap.
}
type PriorityQueue []*Item

func (pq PriorityQueue) Len() int { return len(pq) }
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 = i
	pq[j].index = j
}
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
}

type Q struct {
	pq *PriorityQueue
	ds map[int]int // It has always same value as pq. For random access.
}

func newQ() *Q {
	pq := new(PriorityQueue)
	heap.Init(pq)
	return &Q{
		pq: pq,
		ds: make(map[int]int),
	}
}
func (q *Q) pop() (u, d int) {
	item := heap.Pop(q.pq).(*Item)
	delete(q.ds, item.value)
	return item.value, item.priority
}
func (q *Q) get(u int) (int, bool) { // returns d
	d, ok := q.ds[u]
	return d, ok
}
func (q *Q) set(u, d int) {
	q.ds[u] = d
	for _, item := range *q.pq {
		if item.value != u {
			continue
		}

		item.priority = d
		heap.Fix(q.pq, item.index)
		return
	}
	heap.Push(q.pq, &Item{
		priority: d,
		value:    u,
	})
}
func (q *Q) len() int {
	return len(q.ds)
}

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

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

		out[u] = d
		visited[u] = struct{}{}
	}

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

C++: #define RangeFor(i,n) for(int i=0; i<n; ++i)
#define RvRngFor(i,n) for(int i=n-1; i>=0; --i)

#include <iostream>
#include <vector>
#include <queue>
#include <utility>
#include <limits>

using std::vector;
using std::cin;
using std::priority_queue;
using std::pair;
using std::make_pair;


vector<int> sssp(vector<vector<pair<int, int> > > c, int start_node = 0){
    int n = c.size();
    priority_queue<pair<int, int>, vector<pair<int,int> >, std::greater<pair<int, int>> > pq;
    vector<int> temp_dist(n, std::numeric_limits<int>::max());
    pq.push(make_pair(0, start_node));

    for(;!pq.empty();pq.pop()){
        auto t = pq.top();
        auto d = t.first;
        auto u = t.second;


        if(d < temp_dist[u]){
            temp_dist[u] = d;
            auto k = c[u].size();
            RangeFor(j, k) {
                pq.push(make_pair(d + c[u][j].second, c[u][j].first));
            }
        }
    }

    return temp_dist;
}

int main(){
    int n; cin >> n;
    vector<vector< pair<int,int> > > c(n);
    RangeFor(i, n) {
        int u;
        cin >> u;
        int k;
        cin >> k;
        c[u] = vector<pair<int, int> >(k);
        RangeFor(j, k) {
            int v;
            cin >> v;
            int d;
            cin >> d;
            c[u][j] = make_pair(v, d);
        }
    }

//    RangeFor(i, n){
//        RangeFor(j, c[i].size()){
//            std::cout << c[i][j].first << ' ' << c[i][j].second;
//        }
//        std::cout << std::endl;
//    }

    auto res = sssp(c);
    RangeFor(i, n){
        std::cout << i << ' ' << res[i] << std::endl;
    }
    return 0;
}

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() {
	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 (unsigned int j = 0; j < adj[u].size(); j++) {
			int v = adj[u][j].first;
			if (color[v] == BLACK)continue;
			if (d[v] > d[v] + 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;
	}
}

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;
}

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

#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP0(i,n) for(int i=0, i##_len=(n); i<i##_len; ++i)
#define REP1(i,n) for(int i=1, i##_len=(n); i<=i##_len; ++i)
#define RREP0(i,n) for(int i=n-1; i>=0; --i)
#define RREP1(i,n) for(int i=n; i>=1; --i)

#define SORT(c) sort((c).begin(),(c).end())
#define whole(f,x,...) ([&](decltype((x)) whole) { return (f)(begin(whole), end(whole), ## __VA_ARGS__); })(x)
#define PB push_back
#define MP make_pair
#define SZ(a) int((a).size())
#define EXIST(s,e) ((s).find(e)!=(s).end())
#define CLR(a) memset((a), 0 ,sizeof(a))

inline int toInt(string s) {int v; istringstream sin(s);sin>>v;return v;}
template<class T> inline string toString(T x) {ostringstream sout;sout<<x;return sout.str();}
int gcd(int a,int b){return b?gcd(b,a%b):a;}
int dx[4]={1,0,-1,0};
int dy[4]={0,1,0,-1};

typedef long long LL;
typedef vector<int> VI;
typedef vector<VI> VVI;
typedef vector<string> VS;
typedef pair<int, int> PII;

const int INTINF = 2147483647;
const LL LLINF = 9223372036854775807;
const double EPS = 1e-10;
const double PI  = acos(-1.0);
const int WHITE = 0;
const int GRAY = 1;
const int BLACK = 2;
const int MAX = 10000;

int n;
std::vector<PII> adj[MAX];

struct init{
    init(){
        cin.tie(0); ios::sync_with_stdio(0); cout<<fixed<<setprecision(20);
    };
} init;


void dijkstra(){
  priority_queue<PII> PQ;  // <cost, vertex> のPQ
  int color[MAX];
  int d[MAX];  // d[i] : mincost from s to i
  REP0(i,n){
    d[i] = INTINF;
    color[i] = WHITE;
  }
  d[0] = 0;
  PQ.push(MP(0,0));
  color[0] = GRAY;
  while ( !PQ.empty() ) {
    PII f = PQ.top(); PQ.pop(); //最小となる頂点と重み
    int u = f.second;
    color[u] = BLACK;

    if( d[u] < f.first * -1 ) continue;

    REP0( j, adj[u].size() ){ // uに隣接する頂点をみていく
      int v = adj[u][j].first;
      if ( color[v] == BLACK ) continue;
      if ( d[v] > d[u] + adj[u][j].second ){ // does it renew shortest path to v
        d[v] = d[u] + adj[u][j].second;
        PQ.push(MP(d[v]*-1, v));
        color[v] = GRAY;
      }
    }
  }

  REP0(i,n){
    std::cout << i << " " << (d[i] == INTINF ? -1 : d[i]) << '\n';
  }
}


void input(){
  int u,k,v,c;
  std::cin >> n;
  REP0(i,n){
    std::cin >> u >> k;
    REP0(j,k){
      std::cin >> v >> c;
      adj[u].PB(MP(v,c));
    }
  }
}


int main(int argc, char const *argv[]) {
  input();
  dijkstra();
  return 0;
}