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++: // Last Change: 07/12/2019 03:47:29.
/////////////////////////////////////////////////////////////////////////////
//単一始点最短経路長問題
//以下のプログラムは有向グラフ
/////////////////////////////////////////////////////////////////////////////
#include <algorithm>
#include <array>
#include <bitset>
#include <cmath>
#include <cstdlib>
#include <functional>
#include <iomanip>
#include <iostream>
#include <list>
#include <map>
#include <memory>
#include <numeric>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <vector>

using namespace std;
using ll = long long;

const ll INF = numeric_limits<ll>::max();

struct Node {
  ll cost;
  ll pos;
  Node(ll a, ll b) : cost(a), pos(b) {
  }
  bool operator<(const Node &another) const {
    return cost < another.cost;
  }
  bool operator>(const Node &another) const {
    return cost > another.cost;
  }
};

int main() {
  // n:頂点数
  ll n;
  cin >> n;
  vector<vector<pair<ll, ll>>> edge(n);
  for (ll i = 0; i < n; ++i) {
    ll u, k, v, c;
    cin >> u >> k;
    for (ll j = 0; j < k; ++j) {
      cin >> v >> c;
      edge[u].push_back(make_pair(v, c));
    }
  }

  vector<ll> dist(n, INF);
  //独自関数ならdecltype(func)?
  priority_queue<Node, vector<Node>, greater<Node>> q;
  ll cnt = 0;
  q.push(Node(0, 0));
  while (cnt < n) {
    Node cur = q.top();
    q.pop();
    if (dist[cur.pos] > cur.cost) {
      dist[cur.pos] = cur.cost;
      ++cnt;
      for (auto &&e : edge[cur.pos]) {
        q.push(Node(cur.cost + e.second, e.first));
      }
    }
  }

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

C++: #include <iostream>
#include <cstdio>
#include <algorithm>
using namespace std;
const int maxx=1010;
const int infinity=(1<<30);

int A[maxx][maxx],d[maxx];
bool flag[maxx];

int main (){
	int n,a,b,c;
	cin>>n;
	for(int i=0;i<maxx;i++){
		flag[i]=false;
		d[i]=infinity;
	}
	for(int i=0;i<maxx;i++){
		for(int j=0;j<maxx;j++){
			A[i][j]=infinity;
		}
	}
	for(int i=0;i<n;i++){
		cin>>a>>b;
		for(int j=0;j<b;j++){
			cin>>c>>A[a][c];
		}
	}
	
	d[0]=0;
	while(1){
		int minv=infinity,mini=-1;
		for(int i=0;i<n;i++){
			if(flag[i]==false && d[i]<minv){
				minv=d[i];
				mini=i;
			}
		}
		if(minv==infinity) break;
		flag[mini]=true;
		for(int i =0;i<n;i++){
			if(A[mini][i]!=infinity && flag[i]==false && d[mini]+A[mini][i]<d[i]){
					d[i]=d[mini]+A[mini][i];
			}
		}
			
	}
	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;

const int INF = INT_MAX;
typedef pair<int, int> P;
typedef int long long

struct edge {int to, cost;};

/*
[input]
const vector<vector<edge>> &graph : ??\?????°??????
int s : ?§????
int g : ??????
n*/
int dijkstra(const vector<vector<edge>> &graph, int s, int g ) {
  // ????????????????±?????????????????????????
  vector<int> d(graph.size(), INF);
  // ????§?????????????????????????0????????????
  d[s] = 0;
  // ??????????????????now
  set<P> now;
  // ????§?????????????now????????\
  now.insert(P(0, s));
  
  // now????????????????????§
  while(!now.empty()) {
    // ?????¨?????????????????????pos???????´?
    int pos = now.begin()->second;
    // ?????¨??????????????????????????????????±???????????????????????????????
    if (pos == g) {
      for(int i = 0; i <= g; i++) {
        cout << i << " " << d[i] << endl;
      }
      return INF;
    }
    // now????????¢?´¢?????????????¶????
    now.erase(now.begin());
    // ?????¨??????????????¨???????????¢?´¢
    for(auto ed: graph[pos]) {
      // ??\?¶??????????????????????????????????????????¨??????????????§????????????
      // ??¨??\?¶?????????§?????¨????????????????????????????????§???????????°
      if(d[ed.to] > d[pos] + ed.cost) {
        // now????????\?¶?????????????????±????????????????????????????
        now.erase(P(d[ed.to], ed.to));
        d[ed.to] = d[pos] + ed.cost;
        now.insert(P(d[ed.to], ed.to));
      }
    }
  }
  return INF;
}
  
unsigned main() {
  int num;
  cin >> num;
  vector<vector<edge>> graph(num, vector<edge>());
  int f, n, k, v, c;
  for(int i = 0; i < num; i++) {
    cin >> f >> k;
	if(k == 0) continue;
    for(int j = 0; j < k; j++) {
      cin >> v >> c;
      graph[f].push_back(edge{v, c});
      graph[v].push_back(edge{f, c});
    }
  }
  dijkstra(graph, 0, num - 1);
  return 0;
}