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;

#define MAX 100
#define INFTY (1 << 21)
#define WHITE 0
#define GRAY 1
#define BLACK 2

int n, M[MAX][MAX];

void solve(void) {
    int minv;
    int d[MAX], color[MAX];
    
    for(int i = 0; i < n; ++i) {
        d[i] = INFTY;
        color[i] = WHITE;
    }
    
    d[0] = 0;
    color[0] = GRAY;
    while(true) {
        minv = INFTY;
        int u = -1;
        for(int i = 0; i < n; ++i) {
            if(minv > d[i] && color[i] != BLACK) {
                u = i;
                minv = d[i];
            }
        }
        if(u == -1) break;
        color[u] = BLACK;
        for(int i = 0; i < n; ++i) {
            if(color[i] != BLACK && M[u][i] != INFTY) {
                if(d[i] > d[u] + M[u][i]) {
                    d[i] = d[u] + M[u][i];
                    color[i] = GRAY;
                }
            }
        }
    }
    for(int i = 0; i < n; ++i) {
        cout << i << ' ' << (d[i] == INFTY ? -1 : d[i]) << endl;
    }
}

int main(void) {
    cin >> n;
    for(int i = 0; i < n; ++i) {
        for(int j = 0; j < n; ++j) {
            M[i][j] = INFTY;
        }
    }
    
    int k, c, u, v;
    for(int i = 0; i < n; ++i) {
        cin >> u >> k;
        for(int j = 0; j < k; ++j) {
            cin >> v >> c;
            M[u][v] = c;
        }
    }
    
    solve();
    
    return 0;
}

C++: #include<bits/stdc++.h>
#define INF 1e9
#define MAX_V 100
using namespace std;
int cost[MAX_V][MAX_V];
int d[MAX_V];
bool used[MAX_V];
int V;
void dijkstra(int s){
    fill(d,d+V,INF);
    fill(used,used+V,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;
            }
        }
        
        if(v == -1) break;
        
        used[v] = true;
        
        for(int u=0;u<V;u++){
            d[u] = min(d[u],d[v]+cost[v][u]);
        }
    }
    
    for(int i=0;i<V;i++) cout<<i<<" "<<d[i]<<endl;

    return ;
}

int main(){
    cin>>V;
    int u,k,v,c;

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

C++: #include<iostream>
#include<iomanip>
#include<queue>
#include<string>
#include<stack>
#include<cstdio>
#include<cstdlib>
#include<cmath>
#include<cstring>
#include<cassert>
#include<ctime>
#include<algorithm>
#include<utility>
#include<map>
#include<set>
#include<vector>
#include<functional>

using namespace std;

#ifdef DEBUG
#define dprintf      printf
#define dout(x)      cout<<#x" = "<<(x)<<endl
#define darray(x,n)    {int i;rep(i,n)cout<<#x"["<<i<<"] = "<<*((x)+i)<<endl;}
#define dloop(i,s,g) for((i)=(s);(i)<(g);(i)++)
#define drep(i,n)    for((i)=0;(i)<(n);(i)++)
#define dstop()      scanf("%*c")
#else
#define dprintf      (1)?0:printf
#define dout(x)
#define darray(x,n)
#define dloop(i,s,g) if(1){}else
#define drep(i,n)    if(1){}else
#define dstop()      if(1){}else
#endif

#define F    first
#define S    second
#define pb   push_back
#define mp   make_pair

#define loop(i,s,g) for((i)=(s);(i)<(g);(i)++)
#define rep(i,n)    for((i)=0;(i)<(n);(i)++)
#define all(x)      (x.begin(),x.end())
#define in(T,...) T __VA_ARGS__; impl(__VA_ARGS__);
#define array(T,id,n) T id[n]; rep(i,n)cin>>id[i];

//#define int long long;
#ifndef int
#define INF  (0x7fffffff)
#else
#define LINF (0x7fffffffffffffff)
#endif

typedef long long           ll;
typedef unsigned            ui;
typedef unsigned long long  ull;
typedef pair<int,int>       i_i;
typedef pair<ll,int>        ll_i;
typedef pair<ll,ll>         ll_ll;
typedef pair<double,int>    d_i;
typedef pair<double,double> d_d;

void impl(){};
template <typename T,typename... TS >
void impl(T &head,TS &... tail)
{
  cin>>head;
  impl(tail ...);
}

typedef struct edge
{
  int to;
  int cost;
}Edge;
int V;
#define MAX_V (1000)
vector<Edge> G[MAX_V];
int d[MAX_V];

void djikstra(int s)
{
  int i;
  priority_queue<i_i,vector<i_i>,greater<i_i> > q;
  fill(d,d+V,INF);
  d[s]=0;
  q.push(i_i(0,s));
  while(!q.empty())
    {
      i_i p=q.top();
      q.pop();
      int v=p.S;
      if(d[v]<p.F)
	continue;
      rep(i,G[v].size())
	{
	  Edge e=G[v][i];
	  if(d[e.to]>d[v]+e.cost)
	    {
	      d[e.to]=d[v]+e.cost;
	      q.push(i_i(d[e.to],e.to));
	    }
	}
    }
}

signed main(void)
{
  int n;
  int i,j;
  int u;
  int k;
  Edge e;

  cin>>n;
  rep(i,n)
    {
      cin>>u>>k;
      rep(j,k)
	{ 
	  cin>>e.to>>e.cost;
	  G[j].pb(e);
	}
    }
  djikstra(0);
  rep(i,n)
    {
      cout<<i<<" "<<d[i]<<endl;
    }
  return 0;
}