Go: package main

import (
	"bufio"
	"container/heap"
	"fmt"
	"os"
	"strconv"
)

//make priority queue
type Item struct {
	id       int
	priority int // this state is priority and distans from start
	index    int
}

type PriorityQueue []*Item

func (pq PriorityQueue) Len() int { return len(pq) }

// we want the ascending-priority-queue.
// So we use less than here.
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 = j
	pq[j].index = i
}

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
}

func (pq *PriorityQueue) update(dist int, id int) {
	for _, i := range *pq {
		if i.id == id {
			if i.priority > dist {
				i.priority = dist
			}
		}
	}
}

// the main code
func nextInt(sc *bufio.Scanner) int {
	sc.Scan()
	n, _ := strconv.Atoi(sc.Text())
	return n
}

func dikstra(dist [][]int, n int) []int {
	// preparate priority queue
	inf := 1 << 30
	pq := make(PriorityQueue, n)
	shortests := make([]int, n)
	for i := 0; i < n; i++ {
		pq[i] = &Item{
			id:       i,
			priority: inf,
			index:    i,
		}

		shortests[i] = inf
	}
	pq[0].priority = 0
	shortests[0] = 0
	heap.Init(&pq)

	for pq.Len() > 0 {
		item := heap.Pop(&pq).(*Item)
		shortests[item.id] = item.priority
		for id, d := range dist[item.id] {
			if d != -1 {
				pq.update(item.priority+d, id)
			}
		}
		heap.Init(&pq)
	}
	return shortests
}

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)

	// init
	n := nextInt(sc)
	dist := make([][]int, n)
	for i := 0; i < n; i++ {
		dist[i] = make([]int, n)
		for j := 0; j < n; j++ {
			dist[i][j] = -1
		}
	}

	// std Input
	for i := 0; i < n; i++ {
		u := nextInt(sc)
		k := nextInt(sc)
		for j := 0; j < k; j++ {
			v, c := nextInt(sc), nextInt(sc)
			dist[u][v] = c
		}
	}

	shortests := dikstra(dist, n)
	for i, d := range shortests {
		fmt.Printf("%d %d\n", i, d)
	}
}

C++: #include<iostream>
#include<queue>
#define INF 100000000
using namespace std;
int main(){
  int n;cin>>n;
  int u,k,v,c;
  int mp[101][101],d[101];
  for(int i=0;i<=100;i++){
    d[i]=INF;
    for(int j=0;j<=100;j++)mp[i][j]=INF;
  }
    while(u!=n-1){
    cin>>u>>k;
    for(int i=0;i<k;i++){
      cin>>v>>c;
      if(mp[u][v]>c)mp[u][v]=c;
    }
  }
    d[0]=0;
    queue<int>p;
    p.push(0);
    int mn,s,cnt=n,t[101]={};
    t[0]=1;
    while(!p.empty()){
      s=p.back();
      mn=INF;
      for(int i=0;i<n;i++){
	if(t[i]==0){
	if(d[i]>d[s]+mp[s][i])d[i]=d[s]+mp[s][i];
	  if(mn>d[i])mn=d[i],k=i;
	}
      }
      if(mn!=INF)t[k]=1,p.push(k);
      else p.pop();
    }
    for(int i=0;i<n;i++)cout<<i<<" "<<d[i]<<endl;
    
  return 0;
}

C++: #include<bits/stdc++.h>
using namespace std;
typedef long long ll;
#define loop(i,a,b) for(i=a;i<b;i++)
#define rloop(i,a,b) for(i=a;i>=b;i--)
#define vi vector<int>
#define vl vector<ll>
#define vii vector< vector<int> >
#define vll vector< vector<ll> >
#define vs vector<string>
const int inf=1000000001;
const ll INF=1e16;
#define MOD 1000000007
#define mod 1000000009
#define pi 3.14159265358979323846
static const int WHITE=0;
static const int GRAY=1;
static const int BLACK=2;
static const int N=100;

int n;
vii m(N,vi(N));
vi d(N,inf);

void dijkstra();

int main(){
	int i,j;
	cin>>n;
	int u,k,v,c;
	loop(i,0,n){
		loop(j,0,n){
			m[i][j]=inf;
		}
	}
	loop(i,0,n){
		cin>>u>>k;
		loop(j,0,k){
			cin>>v>>c;
			m[u][v]=c;
		}
	}
	dijkstra();
	loop(i,0,n){
		cout<<i<<" "<<d[i]<<endl;
	}
}

void dijkstra(){
	int i;
	d[0]=0;
	vi color(n,WHITE);
	color[0]=BLACK;
	int u=0,v;
	while(1){
		int minv=inf;
		loop(i,0,n){
			if(color[i]!=BLACK){
				d[i]=min(d[i],d[u]+m[u][i]);
				if(minv>d[i]){
					minv=d[i];
					v=i;
				}
			}
		}
		if(minv==inf){
			break;
		}
		color[v]=BLACK;
		u=v;
	}
	
}

C++: #include <cstdio>
#include <vector>
#include <queue>
using namespace std;
const int MAX_V = 1e+4, INF = 1e+9;
struct edge {int to, cost;};
typedef pair<int, int> P; // 距離, 頂点
int n, d[MAX_V]; vector<edge> G[MAX_V];

void dijkstra(int s) {
  fill(d, d+n, INF); d[s] = 0;
  priority_queue<P, vector<P>, greater<P>> q;
  q.push(P(0, s));
  while(!q.empty()) {
    P p = q.top(); q.pop();
    int now = p.second;
    // 最短距離以外を無視
    if(d[now] < p.first) continue;
    for(int i = 0; i < G[now].size(); ++i) {
      edge e = G[now][i];
      if(d[e.to] > d[now] + e.cost) {
        d[e.to] = d[now] + e.cost;
        // とりあえず追加して、あとで最短距離以外を無視
        q.push(P(d[e.to], e.to));
      }
    }
  }
}
int main() {
  scanf("%d", &n);
  for(int i = 0, u, k; i < n; ++i) {
    scanf("%d %d", &u, &k);
    for(int j = 0, v, c; j < k; ++j) {
      scanf("%d %d", &v, &c);
      edge e = {v, c};
      G[u].push_back(e);
    }
  }
  dijkstra(0);
  for(int i = 0; i < n; ++i) {
    printf("%d %d\n", i, d[i]);
  }
}

C++: #include <iostream>
#include <vector>
#define INFTY 10000000
using namespace std;
int n,G[100][100];
int d[100],flag[100];
vector<int>path;
void dijkstra(){
    path.push_back(0);
    //int distance=0;
    int mini,min;
    while(path.size()<n){
        min=INFTY;
        int index=path.size()-1;
        //distance+=path[path.size()-1];
        for(int i=1;i<n;i++)
        {
            int temp=d[path[index]]+G[path[index]][i];
            if(d[i]>temp)
                d[i]=temp;
        }
        for(int i=1;i<n;i++)
        {
            if(flag[i])continue;
            if(d[i]<min)
            {
                min=d[i];
                mini=i;
            }
        }
        path.push_back(mini);
        flag[mini]=1;
        //distance+=path[path.size()-1];
    }
}
int main()
{
    int u,k,v,c;
    cin>>n;
    for(int i=0;i<n;i++)
    {
        d[i]=INFTY;
        flag[i]=0;
        for(int j=0;j<n;j++)
            G[i][j]=INFTY;
    }
    for(int i=0;i<n;i++)
    {
        cin>>u>>k;
        for(int j=0;j<k;j++)
        {
            cin>>v>>c;
            G[u][v]=c;
        }
    }
    d[0]=0;
    dijkstra();
    for(int i=0;i<n;i++)
        cout<<i<<' '<<d[i]<<endl;
    return 0; 
}

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, M[MAX][MAX];

void dijkstra(){
	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(1){
		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 v = 0;v < n;++v){
			if(color[v] != BLACK && M[u][v] != INFTY){
				if(d[v] > d[u] + M[u][v]){
					d[v] = d[u] + M[u][v];
					color[v] = GRAY;
				}
			}
		}
	}
	for(int i=0;i < n;++i){
		cout << i << " ";
		if(d[i] == INFTY) cout << -1 << endl;
		else cout << d[i] << endl;
	}
}

int main(){
	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;
		}
	}
	
	dijkstra();
	
	return 0;
}