Go: package main

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

const NIL = -1

type Node struct {
	id     int
	weight int
}

func init() {
	sc.Split(bufio.ScanWords)
}

type NodeHeap []Node

func (h NodeHeap) Len() int           { return len(h) }
func (h NodeHeap) Less(i, j int) bool { return h[i].weight < h[j].weight }
func (h NodeHeap) Swap(i, j int)      { h[i], h[j] = h[j], h[i] }

func (h *NodeHeap) Push(x interface{}) {
	*h = append(*h, x.(Node))
}

func (h *NodeHeap) Pop() interface{} {
	old := *h
	n := len(old)
	x := old[n-1]
	*h = old[0 : n-1]
	return x
}

var sc = bufio.NewScanner(os.Stdin)

func scanInt() int {
	num, _ := strconv.Atoi(scanString())
	return num
}

func scanString() string {
	sc.Scan()
	return sc.Text()
}

func init() {
	sc.Split(bufio.ScanWords)
}

func main() {
	n := scanInt()

	list := make([][]int, n)
	weight := make([]int, n)
	for i := range list {
		list[i] = make([]int, n)
		weight[i] = NIL
		for j := range list[i] {
			list[i][j] = NIL
		}
	}

	for i := 0; i < n; i++ {
		u := scanInt()
		k := scanInt()
		for j := 0; j < k; j++ {
			v := scanInt()
			w := scanInt()
			list[u][v] = w
		}
	}

	start := Node{id: 0, weight: 0}
	h := &NodeHeap{start}
	heap.Init(h)

	for h.Len() > 0 {
		node := heap.Pop(h).(Node)
		if weight[node.id] != NIL {
			continue
		}
		weight[node.id] = node.weight

		for i, w := range list[node.id] {
			if w == NIL {
				continue
			}
			heap.Push(h, Node{id: i, weight: w + node.weight})
		}
	}

	w := bufio.NewWriter(os.Stdout)
	for i := 0; i < n; i++ {
		fmt.Fprint(w, i)
		fmt.Fprint(w, " ")
		fmt.Fprint(w, weight[i])
		fmt.Fprintln(w)
	}
	w.Flush()
}

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 << " " << (d[i] == INFTY ? -1 : 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;
}

C++: #include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <algorithm>
#include <string>
#include <sstream>
#include <complex>
#include <vector>
#include <list>
#include <queue>
#include <deque>
#include <stack>
#include <map>
#include <set>
#include <iomanip>
using namespace std;
typedef long long unsigned int ll;
template<typename T> using min_priority_queue = priority_queue<T, vector<T>, greater<T>>;

#define EPS (1e-7)
#define INF (1e9)
#define PI (acos(-1))
#define MOD 1000000007

#define REP(i,n) for(int i=0;i<n;i++)
#define REPS(i,f,n) for(int i=(f);i<(n);i++)
#define EACH(it,v) for(__typeof((v).begin()) it=(v).begin();it!=(v).end();it++)

#define dump(x)  cout << #x << " = " << (x) << endl;
#define debug(x) cout << #x << " = " << (x) << " (L" << __LINE__ << ")" << " " << __FILE__ << endl;

typedef pair<int, int> P;
typedef pair<ll, ll> LP;
typedef pair<int, P> PP;
typedef pair<ll, LP> LPP;

int dy4[]={0, 0, 1, -1};
int dx4[]={1, -1, 0, 0};
int dx8[]={0, 0, 1, -1, 1, 1, -1, -1};
int dy8[]={1, -1, 0, 0, 1, -1, -1, 1};

// http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=ALDS1_12_B&lang=jp

struct edge
{
    int to;
    int cost;
};
vector<edge> G[10005];
int dst[105];

void dij() {
    min_priority_queue<P> q;
    q.push({0, 0});
    dst[0] = 0;

    while(!q.empty()) {
        P f = q.top(); q.pop();
        int v = f.first;
        if (dst[v] < f.second) continue;

        for (edge e : G[v]) {
            if (dst[e.to] > dst[v] + e.cost) {
                dst[e.to] = dst[v] + e.cost;
                q.push({e.to, dst[e.to]});
            }
        }
    }
}

int main() {
    int n; cin >> n;
    REP(i, n) {
        dst[i] = INF;

        int u, k; cin >> u >> k;
        REP(i, k) {
            int v, c; cin >> v >> c;
            G[u].push_back({v, c});
        }
    }

    dij();

    REP(i, n) {
        printf("%d %d\n", i, dst[i]);
    }

    return 0;
}

C++: #include<map>
#include<list>
#include<cmath>
#include<stack>
#include<queue>
#include<vector>
#include<cstring>
#include<iostream>
#include<algorithm>
using namespace std;
#define LOOP1(n) for(int i=0;i<n;i++)
#define LOOP2(n) for(int j=0;j<n;j++)
#define LOOP3(n) for(int k=0;k<n;k++)
#define Psi pair<string,int>
#define Pis pair<int,string>
#define Pii pair<int,int>
// ??????????????????memset(a,0,sizeof(a));
// ?´???°?????? if(x<2)return0;else if(x==2)return1;if(x%2==0)return0;for(i=3;i*i<=x;i+=2){if(x%i==0)return0;}return1;}p440
//vector size();push_back(x);pop_back();begin();end();insert(p,x);erase(p);clear();
//stack  size();top();pop();push(x);emtpy();
//queue  size();front();pop();push(x);empty();
static const int MAX = 100;
static const int INFTY = (1 << 21);
static const int WHITE = 1;
static const int GRAY = 2;
static const int BLACK = 3;
int n; int M[MAX][MAX];
int color[MAX]; int d[MAX]; int p[MAX];
int main(){
	int u, k, v, c, uu, sum = 0;
	cin >> n;
	LOOP1(n){
		LOOP2(n){
			M[i][j] = INFTY;
		}
	}
	LOOP1(n){
		cin >> u >> k;
		LOOP2(k){
			cin >> v >> c;
			M[u][v] = c;
		}
	}
	for (int i = 0; i < n; i++){
		color[i] = WHITE;
		d[i] = INFTY;
		p[i] = -1;
	}
	d[0] = 0;
	while (true){
		int mincost = INFTY;
		LOOP1(n){
			if (color[i] != BLACK && mincost > d[i]){
				mincost = d[i];
				uu = i;
			}
		}
		if (mincost == INFTY) break;
		color[uu] = BLACK;
		LOOP1(n){
			if (M[uu][i] != INFTY && color[i] != BLACK){
				if (M[uu][i] + d[uu] < d[i]){
					d[i] = d[uu] + M[uu][i];
					color[i] = GRAY;
					p[i] = u;
				}
			}
		}
	}
	LOOP1(n){
		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<<" "<<(d[i]==INFTY?-1: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;
}