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>
using namespace std;

static const int MAX = 100;
static const int INFTY = (1<<21);
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

int n,A[MAX][MAX];

void ant();

int main(){
  cin >> n;

  for(int i=0;i<n;i++){
    for(int j=0;j<n;j++){
      A[i][j]=INFTY;
    }
  }

  int a,b,c,d;

  for(int i=0;i<n;i++){
    cin >> a >> b;
    for(int j=0;j<b;j++){
      cin >> c >> d;
      A[a][c]= d;
    }
  }
  ant();
  return 0;
}

void ant(){
  int minv,d[MAX],color[MAX];

  for(int i=0;i<n;i++){
    d[i]=INFTY;
    color[i]=WHITE;
  }
  d[0]=0;
  color[0]=GRAY;

  while(1){
    minv = INFTY;
    int u=-1;
    for(int j=0;j<n;j++){
      if(minv > d[j] && color[j]!=BLACK){
        u=j;
        minv=d[j];
      }
    }
    if(u==-1)break;

    color[u]=BLACK;

    for(int m=0;m<n;m++){
      if(color[m]!=BLACK && A[u][m]!=INFTY){
        if(d[m]>d[u]+A[u][m]){
          d[m]=d[u]+A[u][m];
          color[m]=GRAY;
        }
      }
    }
  }
  for(int i=0;i<n;i++){
    cout << i << " " << (d[i]==INFTY ? -1 : d[i]) << endl;
  }
}

C++: #include <iostream>
#include <algorithm>
#include <cmath>
#include <cstdio>
using namespace std;
#define MAX 10000000

int b[110];
bool used[110];
struct edge{int from, to, cost;};

int solve(int a[110][110], int n){
	b[0] = 0;
	//used[0] = true;
	while(1){
		int v = -1;
		for(int i = 0;i < n;i++){
			if(!used[i] && (v == -1 || b[v] > b[i]))v = i;
		}
		if(v == -1)break;
		used[v] = true;
		for(int i = 0;i < n;i++){
			if(a[v][i] != -1)b[i] = min(b[i], b[v] + a[v][i]);
		}
	}
	return 0;
}

int main(){
	int a[110][110], n;
	fill((int*)a, (int*)(a+110), -1);
	fill(b, b+110, MAX);
	fill(used, used, false);
	cin >> n;
	for(int i = 0;i < n;i++){
		int u, k, c, d;
		cin >> u >> k;
		for(int j = 0;j < k;j++){
			cin >> c >> d;
			a[u][c] = d;
		}
	}
	
	solve(a, n);
	for(int i = 0;i < n;i++){
		cout << i << " " << b[i] << endl;
	}
	
	return 0;
}
/*
5
0 3 2 3 3 1 1 2
1 2 0 2 3 4
2 3 0 3 3 1 4 1
3 4 2 1 0 1 1 4 4 3
4 2 2 1 3 3
*/

C++: #include <stdio.h>
#define N 101
#define INF 0xffffff
#define NIL 0

typedef enum {
  WHITE,
  BLACK,
} color_t;


int main(){
  int n, i, j, u ,k;
  int w[N][N]= {0}; // 0-origin w[u][v] : the weight of "node u -> node v"
  int adj[N][N];  // adj[u][i] : the adjency nodes of node u
  int v;
  int d[N], pi[N];
  color_t color[N];
  int mincost;
  int sum=0;

  for( i = 0 ; i < N ; i++){
    for( j = 0 ; j < N ; j++){
      w[i][j] = INF;
      adj[i][j] = INF;
    }
  }

  scanf("%d", &n);
  for ( i = 0; i < n; i++ ){
  scanf("%d", &u);
  scanf("%d", &k);
    for( j = 0 ; j < k ; j++){
      scanf("%d", &v);      
      scanf("%d", &w[u][v] );
      adj[u][j] = v;
    }
  }

  // initialize single source
  for( i = 0 ; i < N ; i++){
    d[i] = INF;
    pi[i]= NIL;
  }
  const int s = 0;
  d[s] = 0; // s: source
 
  // dijkstra()
  while(1){
    mincost = INF;
    for(i = 0 ; i < n ; i++){
      if( color[i] != BLACK && d[i] < mincost ){
	mincost = d[i];
	u = i;
      }
    }

    if(mincost == INF){
      break;
    }
    
    color[u] = BLACK; 
    for( i=0 ; i < n ; i++){
      v = adj[u][i];
      if( v == INF ){
	break;
      }
      if( color[v] != BLACK && (d[u] + w[u][v]) < d[v] ){
	pi[v] = u;
	d[v]  = d[u] + w[u][v];
      }
    }
    
  }

  // print
  sum = 0;
  for( i = 0 ; i < n ; i++ ){
    if( d[i] != INF ){
      printf("%d %d\n" ,i ,d[i]);
    }
  }

  return 0; // Don't forget return 0
}

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

const int MAX=105;
int state[MAX],N,D[MAX];
vector<pair<int,int>> S[MAX];
priority_queue<pair<int,int>> Q;

void dijkstra(){
    int cnt=1;
    for(int i=0;i<N;i++){
        state[i]=0;
        D[i]=100000000;
    }
    state[0]=1;
    D[0]=0;
    for(int i=0;i<S[0].size();i++){
        Q.push(make_pair(-S[0][i].second,S[0][i].first));
        D[S[0][i].first]=min(D[S[0][i].first],D[0]+S[0][i].second);
    }
    while(1){
        int a=Q.top().second;
        cout<<a<<endl;
        if(state[a]==0){
            Q.pop();
            state[a]=1;
            cnt++;
            for(int i=0;i<S[a].size();i++){
                if(state[S[a][i].first]==0){
                    Q.push(make_pair(-S[a][i].second,S[a][i].first));
                    D[S[a][i].first]=min(D[S[a][i].first],D[a]+S[a][i].second);
                }
            }
        }
        else Q.pop();
        if(cnt==N) break;
    }
    return;
}


int main(){
    
    cin>>N;
    for(int i=0;i<N;i++){
        int l,a;cin>>l>>a;
        for(int j=0;j<a;j++){
            int b,c;cin>>b>>c;
            S[i].push_back(make_pair(b,c));
        }
    }
    dijkstra();
    for(int i=0;i<N;i++){
        cout<<i<<" "<<D[i]<<endl;
    }
}