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++: #include <vector>
#include <queue>
#include <iostream>

using namespace std;

#define NODE_NUM 10000
#define INF 100000

typedef struct Node {
    //????????????????????????????????????
    int idx;
    
    // ????????????????????????????????¨??????????????±
    vector<int> edges_to;    // ?????¨???????????\?¶??????????????????????
    vector<int> edges_cost;  // ?????¨??????????????????
    
    // ??????????????????????????????????????????
    bool done;  // ?¢??????????????????????
    int cost;   // ????????????????????????????????§??????????????????????°??????????
}Node;

Node nodes[NODE_NUM];


struct NodeCompare
{
    bool operator()(const Node &t1, const Node &t2) const
    {
        //?????????????????????????????????????????????????????????????????????????????´?????????????????????????????????
        return t1.cost > t2.cost;
    }
};

void Dijkstra(int node_num, int start_node){
    
    // ?????????
    for (int i =0 ; i < node_num; i++) {
        nodes[i].done = false;
        nodes[i].cost = INF;
        nodes[i].idx = i;
    }

    //????????????????????\???????°?????????????????????????
    priority_queue<Node, vector<Node>, NodeCompare> q;
    
    // ????????????????????????????????????0
    nodes[start_node].cost = 0;
    q.push(nodes[start_node]);
    
    // ??¢?????´???????????????
    while(!q.empty()){
        
        // ?¢????????????????????????????
        Node doneNode = q.top();
        q.pop();
        
        //???????¢?????????????????????????????????????????????¨??±?????????
        if (doneNode.done) continue;
        
        // ?¢????????????°????????????
        nodes[doneNode.idx].done = true;
        
        // ??\?¶?????????????????????±?????´??°??????
        for(int i = 0; i < doneNode.edges_to.size(); i++){
            
            int to = doneNode.edges_to[i];
            int cost = doneNode.cost + doneNode.edges_cost[i];
            if( nodes[to].cost == INF || cost < nodes[to].cost){
                nodes[to].cost = cost;
                if(!nodes[to].done){
                    q.push(nodes[to]);
                }
            }
        }
    }
}

int main( ){
    
    int i, j, n, k, v, c, u;
    scanf("%d", &n);

    for (i = 0; i < n; i++) {
        scanf("%d %d",&u,  &k);
        
        for (j =0 ; j < k; j++) {
            scanf("%d %d", &v, &c);
            nodes[u].edges_cost.push_back(c);
            nodes[u].edges_to.push_back(v);
        }
    }
    
    Dijkstra(n, 0);
    
    for (i=0; i<n; i++) {
        printf("%d %d\n", i, nodes[i].cost);
    }
    
    return 0;
}

C++: // ALDS1_12_C.cpp
// Graph II - Single Source Shortest Path II
#include <iostream>
#include <vector>
#include <algorithm>
#include <cstdio>
#include <queue>
using namespace std;

struct Node {
    int v;
    int c;
    Node(int v, int c): v(v), c(c) {}
};

const int maxN = 10000;
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;
static const int INF = (1<<21);
vector<Node> G[maxN];
vector<int> dist(maxN, INF);
vector<int> p(maxN);
vector<int> color(maxN, WHITE);
priority_queue<pair<int, int>> mq;
int n;

void dijkstra(int x)
{
    dist[x] = 0;
    p[x] = -1;
    mq.push({-dist[x], x});
    while(!mq.empty()) {
        pair<int, int> P = mq.top();
        mq.pop();
        int mindist = -P.first;
        int u = P.second;
        if (color[u] == BLACK) continue;

        for (int i = 0; i < G[u].size(); i++) {
            if (color[u] == BLACK) continue;
            int v = G[u][i].v;
            int c = G[u][i].c;
            if (dist[u] + c < dist[v]) {
                dist[v] = dist[u] + c;
                p[v] = u;
                color[v] = GRAY;
                mq.push({-dist[v], v});
            }
        }
        color[u] = BLACK;
    }
}

int main()
{
//    freopen("in7.txt", "r", stdin);
//    freopen("out7.txt", "w", stdout);
    cin >> n;
    int u, k;
    int v, c;
    for (int i = 0; i < n; i++) {
        cin >> u >> k;
        for (int j = 0; j < k; j++) {
            cin >> v >> c;
            G[i].push_back(Node(v, c));
        }
    }
    dijkstra(0);
    for (int i = 0; i < n; i++) {
        printf("%d %d\n", i, dist[i]);
    }
    return 0;
}

C++: #include <iostream>
#include <queue>
#include <vector>

using WNode = std::pair<uint32_t, uint32_t>;
using WGraph = std::vector<std::vector<WNode>>;
using rWNode = std::pair<uint32_t, uint32_t>;

int main() {
  uint32_t N = 0;
  std::cin >> N;
  WGraph G(N);
  for (size_t i = 0; i < N; i++) {
    uint32_t K = 0;
    std::cin >> i >> K;
    for (size_t j = 0; j < K; j++) {
      uint32_t node = 0, cost = 0;
      std::cin >> node >> cost;
      G[i].push_back({node, cost});
    }
  }

  const uint32_t start = 0;
  std::priority_queue<rWNode, std::vector<rWNode>, std::greater<rWNode>> Q;
  Q.push({0, start});
  std::vector<uint32_t> result(N, -1);
  std::vector<uint32_t> temp(N, -1);
  while (!Q.empty()) {
    uint32_t cost = Q.top().first, current = Q.top().second;
    Q.pop();

    if (result[current] <= cost) continue;
    result[current] = cost;

    for (auto &&g : G[current]) {
      if (result[g.first] != static_cast<uint32_t>(-1)) continue;
      if (temp[g.first] <= g.second + result[current]) continue;
      temp[g.first] = g.second + result[current];
      Q.push({g.second + result[current], g.first});
    }
  }

  for (size_t i = 0; i < N; i++) {
    std::cout << i << " " << result[i] << std::endl;
  }

  return 0;
}