Go: package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

const (
	MAX_N      = 10000
	MAX_WEIGHT = 100000
)

type Edge struct {
	start  int
	end    int
	weight int
}

type ShortestInfo struct {
	edges    []Edge
	shortest int
}

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

	n, err := nextInt(sc)
	if err != nil {
		panic(err)
	}

	shortestList := make([]ShortestInfo, n)
	for i := 1; i < n; i++ {
		shortestList[i] = ShortestInfo{edges: []Edge{}, shortest: MAX_N*MAX_WEIGHT + 1}
	}

	adjacentMatrix, err := createAdjacentMatrix(n, sc)
	if err != nil {
		panic(err)
	}

	sssp([]int{0}, shortestList, adjacentMatrix)
	for _, v := range shortestList {
		fmt.Printf("%d %d\n", v.getEnd(), v.shortest)
	}
}

func (si ShortestInfo) getEnd() int {
	if len(si.edges) == 0 {
		return 0
	} else {
		return si.edges[len(si.edges)-1].end
	}
}

func createAdjacentMatrix(n int, sc *bufio.Scanner) ([][]int, error) {
	adjacentMatrix := make([][]int, n)
	for i := 0; i < n; i++ {
		id, err := nextInt(sc)
		if err != nil {
			return nil, err
		}
		adjacentMatrix[id] = make([]int, n)
		for j := 0; j < n; j++ {
			adjacentMatrix[id][j] = -1
		}
		vertexNum, err := nextInt(sc)
		if err != nil {
			return nil, err
		}
		for j := 0; j < vertexNum; j++ {
			v, err := nextInt(sc)
			if err != nil {
				return nil, err
			}
			c, err := nextInt(sc)
			if err != nil {
				return nil, err
			}
			adjacentMatrix[id][v] = c
		}
	}
	return adjacentMatrix, nil
}

func sssp(nodeStack []int, shortestList []ShortestInfo, adjacentMatrix [][]int) {
	for len(nodeStack) > 0 {
		currentNode := nodeStack[0]
		nodeStack = nodeStack[1:]
		currentShortest := getShortest(currentNode, shortestList)
		adjacents := findAdjacents(currentNode, adjacentMatrix)
		for i := 0; i < len(adjacents); i++ {
			adj := adjacents[i]
			if currentShortest.shortest+adj.weight < getShortest(adj.end, shortestList).shortest {
				setShortest(adj.end, adj, currentShortest, shortestList)
				nodeStack = append(nodeStack, adj.end)
			}
		}
	}
}

func getShortest(node int, shortestList []ShortestInfo) ShortestInfo {
	return shortestList[node]
}

func setShortest(node int, edge Edge, currentShortest ShortestInfo, shortestList []ShortestInfo) {
	newEdges := make([]Edge, len(currentShortest.edges)+1)
	for i := 0; i < len(newEdges)-1; i++ {
		newEdges[i] = currentShortest.edges[i]
	}
	newEdges[len(newEdges)-1] = edge
	shortestInfo := ShortestInfo{edges: newEdges, shortest: currentShortest.shortest + edge.weight}
	shortestList[node] = shortestInfo
}

func findAdjacents(currentNode int, adjacentMatrix [][]int) []Edge {
	adjacents := adjacentMatrix[currentNode]
	edges := []Edge{}
	for i, v := range adjacents {
		if v >= 0 {
			edges = append(edges, Edge{start: currentNode, end: i, weight: v})
		}
	}
	return edges
}

func nextInt(sc *bufio.Scanner) (int, error) {
	sc.Scan()
	return strconv.Atoi(sc.Text())
}

C++: #include<bits/stdc++.h>
using namespace std;
typedef long long ll;
const int INF=0x3f3f3f3f;
inline ll read(){
	ll x=0,f=1;
	char ch=getchar();
	while(ch<'0'||ch>'9'){
		if(ch=='-') f=-1;
		ch=getchar();
	}
	while(ch>='0'&&ch<='9'){
		x=(x<<1)+(x<<3)+(ch^48);
		ch=getchar();
	}
	return x*f;
}
const int maxn=1e4+5;
int n,k,u,v,c;
vector<pair<int,int> >adj[maxn];
void dijkstra(){
	priority_queue<pair<int,int> >PQ;
	int color[maxn],d[maxn];
	for(int i=0;i<n;i++){
		color[i]=0;
		d[i]=INF;
	}
	d[0]=0;
	PQ.push(make_pair(0,0));
	while(!PQ.empty()){
		pair<int,int> f=PQ.top();
		PQ.pop();
		int u=f.second;
		color[u]=1;
		if(d[u]<f.first*(-1)) continue;
		for(int j=0;j<adj[u].size();j++){
			int v=adj[u][j].first;
			if(color[v]==1) continue;
			if(d[v]>d[u]+adj[u][j].second){
				d[v]=d[u]+adj[u][j].second;
				PQ.push(make_pair(d[v]*(-1),v));
			}
		}
	}
	for(int i=0;i<n;i++){
		printf("%d ",i);
		if(d[i]==INF) printf("-1\n");
		else printf("%d\n",d[i]);	
	}
}
int main(){
	n=read();
	for(int i=0;i<n;i++){
		u=read(),k=read();
		for(int j=0;j<k;j++){
			v=read(),c=read();
			adj[u].push_back(make_pair(v,c));
		}
	}
	dijkstra();
	return 0;
}

C++: #include<iostream>
#include<algorithm>
#include<queue>
using namespace std;
static const int MAX = 10000;
static const int INFTY = (1 << 21);
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

int n;
vector<pair<int, int> > adj[MAX];

void dijkstra() {
	priority_queue<pair<int, int> > PQ;
	int color[MAX];
	int d[MAX];
	for (int i = 0; i < n; i++) {
		d[i] = INFTY;
		color[i] = WHITE;
	}
	d[0] = 0;
	PQ.push(make_pair(0, 0));
	color[0] = GRAY;
	while (!PQ.empty()) {
		pair<int, int>f = PQ.top();
		PQ.pop();
		int u = f.second;
		color[u] = BLACK;
		if (d[u] < f.first * (-1)) continue;
		for (int j = 0; j < adj[u].size(); j++) {
			int v = adj[u][j].first;
			if (color[v] == BLACK)continue;
			if (d[v] > d[u] + adj[u][j].second) {
				d[v] = d[u]+adj[u][j].second;
				PQ.push(make_pair(d[v] * (-1), v));
				color[v] = GRAY;
			}
		}
	}
	for (int i = 0; i < n; i++) {
		cout << i << " " << (d[i] == INFTY ? -1 : d[i]) << endl;
	}
}
int main() {
	int k, u, v, c;
	cin >> n;
	for (int i = 0; i < n; i++) {
		cin >> u >> k;
		for (int j = 0; j < k; j++) {
			cin >> v >> c;
			adj[u].push_back(make_pair(v, c));
		}
	}
	dijkstra();
	return 0;
}

C++: #include<iostream>
#include<algorithm>
#include<queue>

using namespace std;

static const int MAX = 10000;
static const int INFTY = (1 << 21);
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;


int n;
vector<pair<int, int> > adj[MAX]

void dijkstra() {
  priority_queue<pair<int, int> > PQ;
  int color [MAX];
  int d[MAX];

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

  d[0] = 0;
  PQ.push(make_pair(0, 0));
  color[0] = GRAY;

  while (!PQ.empty()) {
    pair<int, int> f = PQ.top(); PQ.pop();
    int u = f.second;

    color[u] = BLACK;

    for (int j = 0; j < adj[u].size(); j++) {
      int v = adj[u][j].first;
      if (color[v] == BLACK) {
        continue;
      }
      if (d[v] > d[u] + adj[u][j].second) {
        d[v] = d[u] + adj[u][j].second;
        PQ.push(make_pair(d[v] * (-1), v));
        color[v] = GRAY;
      }
    }

  for (int i = 0; i < n; i++) {
    cout << i << " " << (d[i] == INFTY ? -1 : d[i]) << endl;
  }
}

int main() {
  cin >> n;

  int k, u, v, c;;
  for (int i = 0; i < n; i++) {
    cin >> u >> k;
    for (int j = 0; j < k; j++) {
      cin >> v >> c;
      adj[u].push_back(make_pair(v, c));
    }
  }

  dijkstra();

  return 0;
}

C++: #include <iostream>
#include <queue>
#include <utility>
#include <vector>
using namespace std;

const int MAX_N = 10000;
const int INF = (1 << 21);

int N;
vector<pair<int, int> > A[MAX_N];

void dj() {
  int d[MAX_N], c[MAX_N];

  // (first: distance*-1, second: adjacent)
  priority_queue<pair<int, int> > PQ; 

  for (int i = 0; i < N; i++) {
    d[i] = INF;
    c[i] = -1;
  }

  d[0] = c[0] = 0;
  PQ.push(make_pair(0, 0));

  while (!PQ.empty()) {
    pair<int, int> t = PQ.top(); PQ.pop();
    int cur_n = t.second;
    c[cur_n] = 1;

    if (d[cur_n] < t.first * -1) continue;

    for (int i = 0; i < A[cur_n].size(); i++) {
      int adj_n = A[cur_n][i].first;

      if (c[adj_n] == 1) continue;

      if (d[cur_n] + A[cur_n][i].second < d[adj_n]) {
        d[adj_n] = d[cur_n] + A[cur_n][i].second;
        PQ.push(make_pair(d[adj_n] * -1, adj_n));
        c[adj_n] = 0;
      }
    }
  }

  for (int i = 0; i < N; i++)
    cout << i << ' ' << d[i] << endl;
}

int main() {
  cin >> N;

  for (int i = 0; i < N; i++) {
    int cur_n, k; cin >> cur_n >> k;

    for (int j = 0; j < k; j++) {
      int u, v; cin >> u >> v;
      A[cur_n].push_back(make_pair(u, v));
    }
  }

  dj();

  return 0;
}