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 <iostream>
#include <algorithm>
#define N 100
#define INF 2000000000
using namespace std;

int n, M[N][N], d[N], color[N] = {0};

void Dijk(int s) {
	int min;
	while (true) {
		int u;
	    min = INF;
		for (int i = 0;i < n;i++) d[i] = INF;
		d[s] = 0;

		for (int i = 0;i < n;i++) {
			if (color[i] == 0 && d[i] < min)
				min = d[i];
			u = i;
		}

		if (min == INF) break;

		color[u] = 1;

		for (int v = 0;v < n;v++) {
			if (color[v] == 0 && M[u][v] != INF)
				if (d[v] > d[u] + M[u][v]) {
					d[v] = d[u] + M[u][v];
				}
		}
	}

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

}

int main() {

	for (int i = 0;i < N;i++)
		for (int j = 0;j < N;j++) M[i][j] = INF;

	cin >> n;
	for (int i = 0;i < n;i++) {
		int u,v;
		cin >> u;
		int k;
		cin >> k;
		for (int j = 0;j < k;j++) {
			cin >> v;
			cin >> M[u][v];
		}
	}

	Dijk(0);

}

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

using namespace std;

int main() {

	int INF = 100001;

	int n;
	scanf("%d", &n);

	vector<pair<int, int>> G[n];
	for (int i = 0; i < n; ++i) {
		int from;
		scanf("%d", &from);

		int v;
		scanf("%d", &v);

		for (int j = 0; j < v; ++j) {
			int to;
			int w;
			scanf("%d %d", &to, &w);
			G[from].push_back(make_pair(to, w));
		}
	}

	int C[n];
	for (int i = 0; i < n; ++i)
		C[i] = INF;

	int color[n];
	int WHITE = 0;
	int BLACK = 1;
	for (int i = 0; i < n; ++i)
		color[i] = WHITE;

	priority_queue<pair<int, int>> PQ;
	PQ.push(make_pair(0, 0));
	C[0] = 0;
	while (!PQ.empty()) {
		int u = PQ.top().second;
		PQ.pop();
		color[u] = BLACK;
		for (int i = 0; i < (int) G[u].size(); ++i) {
			auto c = G[u][i];
			if (color[c.first] != BLACK && c.second + C[u] < C[c.first]) {
				C[c.first] = c.second + C[u];
				PQ.push(make_pair(C[c.first] * -1, c.first));
			}
		}
	}

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

	return 0;
}

C++: #include <iostream>
#include <vector>
using namespace std;
#define INF 10000000

int main(){
  int n,k,ti,tv,tc;
  int d[100];
  vector<int> v[100],w[100];
  
  int minc,mi,i;
  bool flg[100];
  
  cin >> n;
  for (i=0;i<n;i++){
    cin >>ti>>k;
    for (int j=0;j<k;j++){
      cin >> tv>>tc;
      v[ti].push_back(tv);
      w[ti].push_back(tc);
    }
    d[i]=INF;
    flg[i]=false;
  }

  d[0]=0;
  while (true){
    minc=INF;
    for (i=0;i<n;i++){
      if (!flg[i]&&d[i]<minc){
	minc=d[i];
	mi=i;
      }
    }

    for (i=0;i<n;i++){
      //cout << d[i] << " ";
    }
    //cout <<" :" << mi << endl;
    if (minc==INF) break;
    flg[mi]=true;
    for (i=0;i<v[mi].size();i++){
      if (!flg[v[mi][i]]&&d[v[mi][i]]>d[mi]+w[mi][i]){
	//cout <<v[mi][i] <<" "<<d[mi]+w[mi][i] << endl;
	d[v[mi][i]]=d[mi]+w[mi][i];
      }
    }
  }
  
  for (i=0;i<n;i++){
    cout << i <<" "<<d[i]<<endl;
  }
  
  return 0;
}

C++: #include<bits/stdc++.h>
using namespace std;
#define INF 1000000000
int main(){
  int n,c,u,k,v,G[100][100],used[100]={},d[100]={},min=0;
  
  cin>>n;
  for(int i=1;i<n;i++)
    d[i]=INF;

  for(int i=0;i<n;i++)
    for(int j=0;j<n;j++)
      G[i][j]=-1;
  
  for(int i=0;i<n;i++){
    cin>>u>>k;
    for(int j=0;j<k;j++){
      cin>>v;
      cin>>c;
      G[u][v]=c;
    }
  }

  while(min!=INF){
    min=INF;
    int idx;
    for(int i=0;i<n;i++)
      if(used[i]!=1 && d[i]<min){
	min=d[i];
        idx=i;
      }
    for(int i=0;i<n;i++)
      if(G[idx][i]!=-1 && used[i]!=1 && d[idx]+G[idx][i]<d[i])d[i]=d[idx]+G[idx][i];
    used[idx]=1;
  }
  
  for(int i=0;i<n;i++)
    cout<<i<<' '<<d[i]<<endl;

  return 0;
}

C++: #include<iostream>
#include<vector>
#include<algorithm>
#define MAX_V 100
#define INF 1e9
using namespace std;
int cost[MAX_V][MAX_V];
int d[MAX_V];
bool used[MAX_V];
int V;
void dijkstra(int s) {
	for (int i = 0; i < MAX_V; i++) {
		d[i] = INF;
		used[i] = false;
	}
	d[s] = 0;
	while (true) {
		int v = -1;
		for (int u = 0; u < V; u++) {
			if (!used[u] && ((v == -1) || d[u] < d[v])) {
				v = u;
			}
		}
		//全ての頂点が到達済み
		if (v == -1) {
			break;
		}
		//集合に新たに頂点を追加
		used[v] = true;
		for (int u = 0; u < V; u++) {
			d[u] = min(d[u], d[v] + cost[v][u]);
		}
	}
}

int main() {
	for (int i = 0; i < MAX_V; i++) {
		for (int j = 0; j < MAX_V; j++) {
			cost[i][j] = INF;
		}
	}
	cin >> V;
	for (int i = 0; i < V; i++) {
		int u;
		cin >> u;
		int k;
		cin >> k;
		for (int j = 0; j < k; j++) {
			int v;
			cin >> v;
			int c;
			cin >> c;
			cost[u][v] = c;
		}
	}
	dijkstra(0);

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